[SOLVED] Are VRM Heatsinks Necessary?

[Regev]

I was going to get the Gigabyte B450M-S2H or B550M-S2H for a Ryzen 3700X. However, someone told me I should get something with 'better heatsinks on the VRM' or something. That seemed weird to me - why do they make MBs without VRM heatsinks then? I googled and found this:

"It depends on the design of the VRM. Most VRMs are designed so that the heat-tabs of the MOSFETs are soldered to the motherboard. The motherboard, itself, forms the heatsink for the VRM. The top surface of the MOSFETs is insulated, so very little heat flows up. However, a lot of a manufacturers still add heatsinks for decoration purposes. Some modern VRMs are now designed so that the heat-tabs of the MOSFETS are on the top surface - these are mainly used in GPUs and laptops. On these, the heatsink is essential, as these VRMs do not use the motherboard as a heatsink."

Is that true? And if so - will the GB B450M/B550M S2H be enough for a non-overclocked 3700X (WraithPrism-ed) without throttling or putting the CPU in danger? Those motherboards have all the features I need, but I won't buy a MB that puts the CPU at risk.

Thanks <3

 

[Darkbreeze]

Most motherboards without VRM heatsinks are meant for use with low end, low TDP processors and low speed memory kits.

Anything geared towards gamers, enthusiasts or high end productivity is likely going to be a CPU and/or memory configuration that requires a significantly beefier VRM configuration and heatsinks, and in some cases even active VRM or chipset cooling as well.

Rarely are VRM or chipset heatsinks "for decoration purposes" so not sure where you got that advice from, but it is contrary to what we normally hold to be true.

No, I would not use the S2H motherboard with the 3700x. I would also SERIOUSLY discourage trying to use the stock cooler with it. It WILL be insufficient AND problematic. The wraith coolers basically, suck. Yes, they are better than stock coolers from past years, but they'd have to be, because there are a lot more cores and much higher thermal design power ratings than for most previous processor generations on most models.

It's not really a matter of "risk", it's a matter of "why does my performance suck" and the performance will suck because the CPU will be automatically throttling half the time because it cannot remain within the thermal envelope required to maintain it's boost profiles, and it's boost performance is where the majority of it's performance will be coming from. Regardless of CPU model or brand, clock is still king, and without decent boost behavior the performance will suffer for most usage.

Plan for a better board, and for aftermarket cooling. You'll never get by with the stock cooler on that CPU, especially not with a budget motherboard, but even with a good one it would still be very advisable.

 

[ocer9999]

Genereally the mobos that dont have any VRM heatsinks they are budget motherboards and with that said, they also come with weaker VRMs, which is silly..
You have a decent budget B550 like the Asrock Phantom 4 which has a heatsink on the main VRM and cost just over 100$. You might want to take a look on that one.

 

[Darkbreeze]

The Phantom 4 isn't particularly great. I think the LEAST capable motherboard I'd be looking at would be something like the Pro4, for the 3700x. Better would be something like the Tomahawk, Steel legend, Extreme, Aorus Pro or Master, ASUS A series, something in the mid tiered ranges or higher, whatever the brand and model.

A budget board is going to get you exactly, or less than, that. Budget. Budget normally means cutting something out in order to accommodate an imposed price restriction and you're never going to get the desired result combining a performance part with a budget part, or at least, very, very seldom.

 

[Regev]

Is an aftermarket cooler really necessary? The Prism actually seems robust on the 3700X, even 3900x:

'I'm using the stock cooler and the paste that came on the stock cooler. My temps at idle are around 30c. Single core stress temps in the upper 40's. And multi-core stress temps are in the high 60's close to 70c. Plenty fine as long as you have a good case with great airflow."

'The performance equivalent is a 35$ good aftermarket air cooler, with more noise.'

View: https://www.youtube.com/watch?v=DBQ1RUeV_oo

View: https://www.youtube.com/watch?v=2Wzhh3zH9Hs
(cools even a 3900x with no drop in performance, 07:26)


Where I'm from it's totally different prices:

GIGABYTE B550M S2H - $116
GIGABYTE B550M DS3H - $137
ASUS PRIME-B550M-K - $141
ASUS PRIME-B550M-A - $162
GIGABYTE B550M-AORUS-PRO - $168
ASUS PRIME-B550M-PLUS - $180
GIGABYTE B550 GAMING X at $195

Anything else is $200-400

 

[Darkbreeze]

I've built five Ryzen systems ranging from the 3600 to the 3700x. In every case, the stock cooler failed to be adequate in keeping the CPU below the recommended thermal ceiling when running a not-overclocked, steady state, thermal stress test via no-AVX Prime95 Small FFT settings.

Besides which, even in normal usage, with no stress tests running, the CPUs were all seen to be experiencing highly bursty behavior into the low 80's despite having already tweaked the configurations and disabled the PBO2 profiles, but leaving the stock XFR2 profile enabled.

No less than maybe ten others here on this forum, all of whom are HIGHLY experienced systems builders and tweakers, have experienced similar problems with very annoying up-down up-down clock behavior and mildly borderline excessive thermal patterns, all of which were resolved by switching to various forms of aftermarket cooling. In my case, three of them got Thermalright True spirit direct 140 coolers, one got a Noctua NH-U14S and two others got 280mm Corsair AIO coolers. All problems resolved, ESPECIALLY the HIGHLY annoying hum and up down droning of the stock cooler which is enough to drive a room full of recovering alcoholics into heroine addiction.

Keep in mind, EVERY SINGLE one of the reviews and pitches you hear from various reviewers are to some degree generally based on the fact that those reviewers rely on those companies sending them review samples so they are going to be at least moderately inclined to offer favorable comments about those products, even if they personally don't believe them to be worthwhile, which I know for a fact many of them do not having spoken to some of said reviewers.

I, and others here, on the other hand, care not what any of these companies think about what I find to be truth regarding any given product, because they ain't doing nothing for me and to be honest, I just don't give a damn whether they like it or not. If you don't like, fix your products so there isn't anything so basically annoying to complain about, and then I'll say nice things about it. I'd LIKE to like the Wraith coolers, but my experience with five of them tells me that in truth, they are highly overrated, and that they just plain suck. Sure, they WILL technically keep your CPU from burning up, but 40% of that is the fact that the platform has very active boost/throttle behavior to help that out.

Of the boards you listed there, I'd take a close look at the B550M Aorus Pro, which from what I've seen so far has a very good feature set and if anything like the prior gen Aorus pro, is a pretty good board.

 

[Regev]

@Darkbreeze Thanks man. Is there any chance you're talking about the Stealth / Spire coolers and not the Prism? I read so many favorable Prism reviews and comments (on reddit, not some commercial channel), that it comes as quite a shock to me that at they were all plain wrong.

 

[kurdtnz]

Also,the Prism's are very loud! I have one on a 3600X and even when just browsing or watching netflix etc it continuously throttles up and down,(yes,it's doing it's job but it is very,very audible.)

 

[Darkbreeze]

I'm talking about ALL of the Wraith coolers. The better coolers ONLY come on the CPUs that are higher core count, higher TDP models, so from top to bottom the performance is still going to be commensurate with the TDP (Thermal design power) of the specific CPU.

Wraith spire for example, with the 3600x, doesn't perform any worse, or better, with that 6/12 CPU than the Wraith Prism that comes with the 3700x which is an 8/16 model. Yes, the Prism is a more capable cooler AND if it came on the 6/12 models it might be a different story, in one regard, which is overall thermal capability, but the fact that it doesn't and it comes with a CPU that has an additional 2/4 cores/threads means that in reality it doesn't perform any better on that CPU than the Spire does on the 6/12 models.

And, besides which, none of that changes the fact that the harmonics and monotonous ramping up and down of the fan on ALL these coolers, is intolerable. I don't care who says they are good, they can have them, and stick them............well, you get the idea. After five minutes of listening to the Spire on the first Ryzen build I did I was calling the owner to tell them and then came and listened to it and flat out said, "take it off and get something different. I don't want to have to listen to that for the next two or three years".

And when I built the system with the Prism, it was the same process again with that owner, for which I'm glad, because I don't want to be responsible for driving anybody into the loony bin. I know I would be if I had to listen to the constant up-down sound at that particular harmonic for very long.

So, whatever. If you don't mind it, more power to you. For me, and most the builders around here that have had the opportunity to build with one of them and listen to it for themselves, they quickly change their previous positions and yes, we all felt like they were ok based on reviews and feedback from reviewers prior to having actually had to sit and listen to them and look at the numbers ourselves.

 

[Regev]

@Darkbreeze Oh, <Mod Edit>. You got me convinced. Although notice the 3700X is 65TDP - just like the 3600, and unlike the 3600X. But if noise levels are that crazy, no way I'm subjecting myself to this misery.

Which QUIET cooler would you pick up then for a 3700X (no overclocked planned, I mean not manual. I heard AMD does it automatically these days)?

I was thinking the Noctua L12S ? I like that it's not so tall. Is it top-notch in performance and quietness? I'm going to mount the motherboard underneath the desk (no case).

 

[Darkbreeze]

What can you realistically afford to spend on a cooler?

As to the TDP, yes, that is something I've been trying to yell at AMD about, because it's patently impossible for two different CPUs that use the same Zen2 cores and have the same peak boost clock profiles to have not only the same TDP, but a higher TDP on the 3600x, when the 3700x with the same maximum boost speed, and very similar all core boost speeds.

Truthfully, since AMD doesn't list the all core boost speeds and we've REPEATEDLY seen with our own eyes that both the 3600x and 3700x tend to hit an all core ceiling at about 4Ghz, there must be some seriously creative accounting going on at AMD to come up with only 65w on the 3700x. I should have used my kill-a-watt on the 3700x I had here because I suspect that it's more like a 95w TDP at all core full load. With PBO enabled, that changes even more and all bets are off because AMD's figures are only accounted for based on the stock XFR2 profile, not the PBO2 profile, from what I can discern. I think PBO/PBO2 makes the whole argument a moot point because it changes all the numbers.

 

[Regev]

@Darkbreeze
So it's just a number, whereas in reality its the same power draw and temps of the 3800X? Speaking of the 3800X, I can get this one for just $35 more. Worth it?

As for the cooler - no budget. I could spend as much as needed on something if its super quiet and if I could carry that cooler along with me onto the next CPUs in the future. Sounds like a good investment. Noctua L12S?

This thread is turning into a full time job for you Thank you so much.

 

[madmatt30]

@Darkbreeze
So it's just a number, whereas in reality its the same power draw and temps of the 3800X? Speaking of the 3800X, I can get this one for just $35 more. Worth it?

As for the cooler - no budget. I could spend as much as needed on something if its super quiet and if I could carry that cooler along with me onto the next CPUs in the future. Sounds like a good investment. Noctua L12S?

This thread is turning into a full time job for you Thank you so much.

You say it's going to go under your desk?
Is this in an open environment or is it going to be internal?

Some idea of what you actually mean would be helpful regarding a cooler.

Downblowers do have their uses but it depends on where you board is going to be sitting and how much space you have around it etc.

If the area at the from and rear of the board are going to be open you would be better off with a tower cooler for its directional airflow rather than a downblower imo.

Depends on what you're actually meaning by 'under the desk' though

And no, the 3800x isn't worth paying $35 more for btw.

 

[Regev]

You say it's going to go under your desk?
Is this in an open environment or is it going to be internal?

Some idea of what you actually mean would be helpful regarding a cooler.

Downblowers do have their uses but it depends on where you board is going to be sitting and how much space you have around it etc.

If the area at the from and rear of the board are going to be open you would be better off with a tower cooler for its directional airflow rather than a downblower imo.

Depends on what you're actually meaning by 'under the desk' though

And no, the 3800x isn't worth paying $35 more for btw.

Something like this:

View: https://www.youtube.com/watch?v=AHEQTHDkusk


I've had this idea for a long time. Googled and found this guy has done it

Hopefully AMD will release their 4000G APUs soon enough, and I could just sell the 3700X and RX580 (which I had lying around) and have a real low-profile under desk.

 

[Darkbreeze]

That guy is an idiot and SOMETHING at some point or other IS going to fail on that board due to not using any standoffs at all. Doesn't matter that it's a wood substrate rather than metal, there are other reasons for using standoffs than just shorting directly to the case. It allows clearance for components on the backside of the board like the backplate, traces, solder points AND to allow at least SOME measure of air to be present between the motherboard and whatever it is mounted to because everything tends to heat up, not just the CPU, VRMs and chipset.

If you do something like this, be sure to incorporate the use of standoffs into the design. You may need to find and order specialty standoffs in order to be able to securely screw them into the wood surface as the fine, rather short threading on regular standoffs probably isn't enough to be secure unless you install some kind of metal receiver with matching threads into the wood first, OR tap the wood VERY carefully and then harden the threads using several applications of super glue, and then re-chase the threads afterwards with your tap again. There are also T-screw anchors with "teeth" that will bite into the wood but finding ones with the right thread size and pitch for standoffs might require some real investigative work.

 

[madmatt30]

You can buy acrylic open air trays for around $20 from ebay.

That or as I've seen done, buy a second hand old atx case for cheap and cut the tray out of it.
Drill 4 extra holes in the corners and countersink screw it to a 5mm piece of mdf.
Easiest and probably the cheapest option.

 

[Darkbreeze]

Yep, lots of "right" ways to do it. The way shown in that video though, screwed directly to the wood with no standoffs, is a disaster waiting to happen.

 

[Regev]

@Darkbreeze @madmatt30 Thanks for the advice guys! Yep I did plan to use standoffs of course (and had the same visceral response you had to the video hahah). However I have to first decide on a cooler and motherboard.

As for the cooler, was thinking the L12S? It's low profile enough that it won't protrude too much, but does it cool as well as the, say, U14S? Remember, im dealing with the 3700X - not a 10900K

As for the motherboard, look what I found. It's so strange:

https://linustechtips.com/main/topic/1137619-motherboard-vrm-tier-list-v2-currently-amd-only/

The B450M S2H and DS3H's VRM appears to be Tier E, claiming its enough to max the 3600 but not the 3700x (on little ambient airflow). The B450H is even worse - at tier F (good for 3300X). However, and here's what's strange.

B550 DS3H gets Tier D (good to max the 3700X on little ambient airflow), while the cheaper B550 S2H gets a Tier C (good to max the 3900X on little ambient airflow), same as the AORUS Pro or the MSI X570 Pro Carbon. How is that possible?!

That's the cheapest board where I come from. Is its VRM really so good for its price, even better than its DS3H brother and as good as the B550 AORUS Pro ?

 

[madmatt30]

That guy is an idiot and SOMETHING at some point or other IS going to fail on that board due to not using any standoffs at all. Doesn't matter that it's a wood substrate rather than metal, there are other reasons for using standoffs than just shorting directly to the case. It allows clearance for components on the backside of the board like the backplate, traces, solder points AND to allow at least SOME measure of air to be present between the motherboard and whatever it is mounted to because everything tends to heat up, not just the CPU, VRMs and chipset.

If you do something like this, be sure to incorporate the use of standoffs into the design. You may need to find and order specialty standoffs in order to be able to securely screw them into the wood surface as the fine, rather short threading on regular standoffs probably isn't enough to be secure unless you install some kind of metal receiver with matching threads into the wood first, OR tap the wood VERY carefully and then harden the threads using several applications of super glue, and then re-chase the threads afterwards with your tap again. There are also T-screw anchors with "teeth" that will bite into the wood but finding ones with the right thread size and pitch for standoffs might require some real investigative work.

@Darkbreeze @madmatt30 Thanks for the advice guys! Yep I did plan to use standoffs of course (and had the same visceral response you had to the video hahah). However I have to first decide on a cooler and motherboard.

As for the cooler, was thinking the L12S? It's low profile enough that it won't protrude too much, but does it cool as well as the, say, U14S? Remember, im dealing with the 3700X - not a 10900K

As for the motherboard, look what I found. It's so strange:

https://linustechtips.com/main/topic/1137619-motherboard-vrm-tier-list-v2-currently-amd-only/

The B450M S2H and DS3H's VRM appears to be Tier E, claiming its enough to max the 3600 but not the 3700x (on little ambient airflow). The B450H is even worse - at tier F (good for 3300X). However, and here's what's strange.

B550 DS3H gets Tier D (good to max the 3700X on little ambient airflow), while the cheaper B550 S2H gets a Tier C (good to max the 3900X on little ambient airflow), same as the AORUS Pro or the MSI X570 Pro Carbon. How is that possible?!

That's the cheapest board where I come from. Is its VRM really so good for its price, even better than its DS3H brother and as good as the B550 AORUS Pro ?

I'm not convinced with a 5+3 phase it's anywhere near physically as good component wise.

These are fairly short term tests, who knows how it will hold up with prolonged use over time.

Minimum I'd look at is the asrock b550 steel legend or msi b550 gaming plus, the reinforced pci express slots as well as the decent vrm setup play a part in that choice.

Spending the money on a 3900x honestly the MSI tomahawk b550 would probably be first choice.
The component quality on that board & the vrm setup are top notch.

Don't skimp on the board with a 3900x!

 

[Darkbreeze]

That's no tier list. That's a pile of crap. THIS, is a tier list, or more specifically, NOT a tier list but a comprehensive list of what components are used on each board and how they compare in terms of configurations.

https://docs.google.com/spreadsheet...FnsZYZiW1pfiDZnKCjaXyzd1o/edit#gid=2112472504

 

[Regev]

@madmatt30 3700x, not 3900x
I went on @Darkbreeze 's linked list. What a rabbit hole! Here are the VRMs on each of the >~$200 boards available in my country, listed by number of true phases:

1. MSI B550M-PRO-VDH-WIFI - 6 True, 4+2 - $202
2. MSI MAG B550M BAZOOKA - 6 True, 4+2 - $217
3. ASRock B450M-Pro4 - 6 True (9 Virtual), 3(x2)+3 - $99
4. ASUS TUF-GAMING-B550M-PLUS - 6 True, 4(x2)+2 - $191
5. MSI MPG B550 Gaming Plus - 7 True (12 Virtual), 5+5+2 - $237
6. Gigabyte B550M S2H - 8 True, 5+3 - $113
7. Gigabyte B550M DS3H - 8 True, 5+3 - $135
8. Gigabyte B550M AORUS PRO - 8 True (13 Virtual), 5(+5)+3 - $168
9. Gigabyte B550 GAMING X - 8 True (13 Virtual), 5(+5)+3 - $190
10. Gigabyte B550 AORUS Elite - 8 True (14 Virtual), 6(+6)+2 - $207

It's worth mentioning that all the Gigabyte (except last one) and MSI boards use the EXACT same main VRM components from ONSemi. As for the controller, MSI uses Richtek while the Gigabytes use Renesas.

What should I get from this, besides the fact that MSI is crazy overpricing? Which one is the best bang for the buck to carry the 3700X? After checking that list I'm leaning more and more toward the S2H (or the AORUS Pro, just not sure if the only difference (phase doublers) is worth the extra 50%).

By the way, my comment on VRM heatsinks comes from @InvalidError, who wrote on a post here in the forum:

"Technically speaking, there is nothing wrong with a plain four phases VRM either: the CPU draws around 80A peak, divided between four phases, that's 20A average, and with FETs that have 4mOhm Rdson, that's 1.6W worth of loss per phase. If you use two pairs of FETs per channel, average current through each pair drops to 10A, allowing you to use cheaper FETs with 6mOhm Rdson while still reducing power dissipation to 0.6W per pair (1.2W per phase when driving two pairs per phase output) and making the VRM 1.6W (0.4W per phase, x4) easier to cool. Those VRM heatsinks are mostly decorative: they are clamped on top of the VRM's plastic/epoxy encapsulation. Most of the real VRM heatsinking is provided by the motherboard's power and ground planes."

Thanks again guys,
You're awesome.

 

[Darkbreeze]

Those prices didn't look like that three months ago. Then, those MSI boards were about fifty bucks cheaper than the least expensive Gigabyte board with a similar configuration as what you could get on the B450 Tomahawk (And Max), B450 Gaming Plus and B450 Pro Carbon, all of which have excellent VRM configurations.

The B550 boards are of course, a different situation because they ARE PCIe 4.0 capable which board manufacturers clearly said were going to cost more than previous generation chipsets due to the supposedly added expensive of making them PCIe 4.0 capable, and the current conditions with the supply chain due to Covid 19 considerations.

So if two boards have the same VRM configurations and whatever available reviews there are don't indicate that the less expensive model has some other kind of problem, then go with what is less expensive so long as it has ALL other features you require or desire. If there are no reviews for a given model, then I'd either wait until there are OR understand that one a lot of less expensive budget models there will NEVER be an in depth, reputable review for it because manufacturers tend to not send out review samples of those kinds of boards and reviewers tend to not buy them for reviewing because there are much better options more worthy of spending review dollars on.

This board would do perfectly well, great in fact, for the 3700x, and is substantially less expensive than what "I" am seeing available in your region for the B550 boards. You must be seeing resources on hardware that PCPP is not sourcing for pricing.

PCPartPicker Part List

Motherboard: MSI B450 TOMAHAWK MAX ATX AM4 Motherboard (₪684.11 @ Newegg Israel)
Total: ₪684.11
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2020-08-05 12:11 IDT+0300

 

[madmatt30]

ASRock B450-Pro 4 is a good board IF you can ensure its updated to run gen 2 ryzen before buying.

It may be only a physical 3 phase but the phase doubling just works, and it works well.

Its also one of the cheapest boards on there.

Own that board myself, running a ryzen 7 albeit a gen one 1700

It is overclocked to 3.9ghz and it runs well, no issues at all.

That said, I bought that board before either gen 2 ryzen or b550 were released. If buying now I'd go with a b550 without a doubt.

It depends if you ever have upgrade plans regarding a 12c/12 thread ryzen or you expect to run that 3700x for the foreseeable futur3+e.

 

[Regev]

Here's the B450 Tomahawk's VRM @Darkbreeze said was excellent:

Here's the one on the B550 S2H:

And here's the Bazooka B550:

It seems to me as if people perceive the S2H to be inferior in quality because of its low price. But the power specs look better than the Bazooka which is double the price (unless 4+2 with x2 on the high & low sides is better than 5+3 with x1). Could it be that Gigabyte priced it that way, not because of its quality, but simply to have a performant product on the low-end market?

@madmatt30 Oh, nice man! Thanks. Which cooler are you using? I did look into native vs virtual phases and found this (on v12-phase VRMs):

"While still better than regular 6 phase parts, they’re not as efficient as true 8 or 10 phase VRMs. They induce a delay and reduce the frequency of supplied current in half. Furthermore, only one of the two can be switched on at a time. The first one sees a modest delay but the second one is usually delayed by half a cycle, and in terms of precision, even the former is rather substantial. While multi-phase VRMs kick in instantly, or one after the other without a notable delay in between, pseudo-phases or doublers induce a latency which reduces the overall efficiency. Again, a 5 phase VRM doubled to 10 is less efficient than a native 7 or 8 phase VRM. But a 10 phase (doubled) VRM is still better than a 5 phase and is a cheap trick to allow a higher power draw."

In case someone finds this useful.

 

[madmatt30]

Here's the B450 Tomahawk's VRM @Darkbreeze said was excellent:

Here's the one on the B550 S2H:

And here's the Bazooka B550:

It seems to me as if people perceive the S2H to be inferior in quality because of its low price. But the power specs look better than the Bazooka which is double the price (unless 4+2 with x2 on the high & low sides is better than 5+3 with x1). Could it be that Gigabyte priced it that way, not because of its quality, but simply to have a performant product on the low-end market?

@madmatt30 Oh, nice man! Thanks. Which cooler are you using? I did look into native vs virtual phases and found this (on v12-phase VRMs):

"While still better than regular 6 phase parts, they’re not as efficient as true 8 or 10 phase VRMs. They induce a delay and reduce the frequency of supplied current in half. Furthermore, only one of the two can be switched on at a time. The first one sees a modest delay but the second one is usually delayed by half a cycle, and in terms of precision, even the former is rather substantial. While multi-phase VRMs kick in instantly, or one after the other without a notable delay in between, pseudo-phases or doublers induce a latency which reduces the overall efficiency. Again, a 5 phase VRM doubled to 10 is less efficient than a native 7 or 8 phase VRM. But a 10 phase (doubled) VRM is still better than a 5 phase and is a cheap trick to allow a higher power draw."

In case someone finds this useful.

It looks like gigabyte may have done what they've done in the past & dropped a board with a better spec power delivery system than the competition at a lower price with no fanfare.

They did that back in the am3 days with the 970 ud3p, a cheap full atx board that just crushed the competition when it came to vrm setup and overclocking (which mattered far more with a low ipc power hungry cpu like the fx series)

I don't know, the tomahawk has higher spec, lower resistance mosfets than the bazooka and gigabyte, both the msi boards have doubled up mosfets on both main phase and soc, but with a sub 100w cpu it doesn't honestly matter.

Even at full pbo with every core full tilt the 3700x doesn't top 130w.

Any of the boards listed will do honestly as long as they offer the ports and slots that you require.

The gigabyte does look more and more promising in that respect.
It isn't however as good as the Tomahawk in any way, its not made to be.

Cooler? Im using a silentium Fortis 3 he 1425 - its a 140mm tower and somewhat of a beast if you can get it at the right price.
Would work wonderfully open air because its damn near silent.

Under stress testing my ryzen 7 has never topped 60c and the fan has never been above 1000rpm.