Question Radiator Size/Placement

[BigObamus]

Hey there.

I'm currenty building my first PC and already bought all components, but decided to change my air cooler (be quiet! Dark Rock Pro 4) to an All-in-One Water Cooler by Corsair, as the DRP4 is sitting directly over the RAM, which kinda kills the point of having RGB RAM und may cause thermal problems in the future. I'm not sure yet, which type of cooler (3 fans or 2 fans) to buy and where to place it for optimal airflow. The budget is not limited.

My components:

• MSI Z390 Gaming Pro Carbon AC
• Intel i7 9700K (OC)
• MSI GTX 1080 Ti Gaming X (OC)
• 16GB Corsair Vengeance RGB PRO 3200Mhz RAM
• Corsair Obsidian 500D RGB SE Case
• be quiet! Straight Power 11 650W
• 4x Corsair LL120 fans, 2x Corsair LL140 fans

The build is currently paused, as I want to continue when I bought the new cooler because of cable management, but the build is mostly done, except cable connecting. If you got any suggestions or ideas, let me know, thanks.

 

[Lutfij]

Front would be the place I'd mount the AIO's regardless of size to have cooler ambient air fed through the rad. You can have the fans in push o have the light spill from the front fascia.

 

[BigObamus]

But wouldn't that just blast hot air into the case? The fans on the top and back are for outtake, so there would only be hot air going into the case, but no cool air going in.

 

[geofelt]

Locating an AIO radiator is a catch 2 situation.
As you correctly pointed out, a front intake mount will send heated air into the case heating up the motherboard and also the airflow used for the gpu cooler.

OTOH, if you mount the radiator on top, exhausting to outside, the radiator will get hotter air to use and cpu cooling will not be as good.
Also, mounting on top will negate the cleansing action of a positive pressure cooling from filtered front intakes.
On balance, I agree with a front mount.

The DRP4 is a nice cooler with a problem with tall ram.
You could solve that with an equally good performing noctua NH-D15s.
The noctua clears tall heat spreaders and also is offset to clear a graphics card mounted in the first pcie x16 slot.

 

[BigObamus]

Before buying i couldn't decide between the Noctua and be quiet!, as they were both equally powerful, but I choose the DRP4, as I have tempered glass and the Noctua one would ruin the look (I didn't want to spend 50$ on Noctua Chromax products to make it look good. Now I decided against air coolers, as they block my RAM and back fan and create a very sturdy look.

Now I have to decide between a 360mm AiO for the front or 280mm for the top. I see many people arguing that front mounting is better for the airflow, even though it kinda seems paradoxic to me. I guess will try front mounting.

Also, have three spare LL120 RGB fans, could I mount those as well as the radiator fans to each side to create even more cooling power? And what would be a great 360mm AiO, currently looking at the Corsair H150i Pro?

 

[rubix_1011]

Cooler Master ML360R did better than the H150i Pro. Also did better than the NXZT Kraken X72.

I did the review: https://www.tomshardware.com/reviews/coolermaster-masterliquid-ml360r-rgb,5736.html

Although, the NZXT has a decent software suite, as does the H150i Pro.

More importantly, you're overthinking the entire process - most AIOs are (dozens of vendors) are actually manufactured by the same few companies and then rebranded to 'Corsair', 'Cooler Master', 'NZXT', 'DeepCool', etc. The only differences are the fans they use and any software for controlling the cooler. Otherwise, pumps and radiators are pretty much all the same for the few manufacturers: https://www.gamersnexus.net/guides/2122-who-actually-makes-liquid-coolers-oems

This link is a few years old with some minor changes, but otherwise still shows what really lies beneath that sticker.

 

[SgtScream]

The radiator's mounting position depends on the hardware components you're using. If you mount the rad in the front, you'll get great cpu temps from the intake air, however your graphics card may run hotter. Adversely, you could mount the rad on the top and the front intake will drop gpu temperatures however heat will rise into the radiator causing higher cpu temps. AIO mounting is dependent on the situation and components used. You're going to have to find out which config works best for your situation by trying the different mounting configs. The TDP of the i7 9700k is significantly less than the i9 9900k, so it is less likely you'll run into temp issues with either configuration. Therefore since graphics cards generally run hotter, I would mount the rad on the top to ensure the front intake fans are unobstructed for the graphics card.

 

[geofelt]

Liquid cooling is just air cooling with a different location for the radiator.
In theory, a 280 radiator will be comprised of two 140mm radiators.
The surface area is comparable to the surface area of three 120mm radiators.
(the area of two 140mm diameter circles is about the same as three 120mm circles)
In deciding between the two, it probably does not make all that much difference.
Usually, 140mm fans turn slower and are quieter.

I might also point out that the NH-D15s also has two 140mm radiators.
The efficiency of heat transfer to liquid in a pump should be better than to the fluid in an air cooler.
But, ultimately whatever heat there is must be expelled to the outside world through the heat exchange radiators.

Don't beat yourself up about this decision.
All of your alternatives will do the job equally well.
The i7-9700K has soldered heat spreaders and will run cooler than you might think so long as you are not seeking a max overclock.

A plus for the NH-D15s is that it costs half as much and will be quieter.

 

[Karadjgne]

Yes, much over thinking.

My case is a fractal design R5, not ranked as very good for airflow. I used a nzxt X61 280mm on an i7-3770K at 4.9GHz and a asus gtx970 @ 124%oc. Started out with the rad up top, push fans. No rear exhaust, just 2x 140mm on the rad as exhaust, 2x stock 140mm intakes. On a whim, tested by moving the rad to front intake with fans in pull (pull has better temp results for slow fans, push for fans above @ 1200rpm).

The case temps went up 2°C after the move. Gpu temps went up 2°C after move. Cpu temps dropped 2°C after move. All this under stress testing cpu/gpu simultaneously at 100%loads.

Conclusion: front intake or top exhaust really does not matter, overall temps will be equitable with relatively ok airflow or better as heat energy will be removed faster than it gets the chance to do any real heating of the air that moves it. Same theory as heating a pot of water, just because the pot is 400° doesn't mean the water instantly becomes 400°, it takes a while and that water can be changed in a constant flow and never truly get hot.

Overall results are, unless benchmark temps are a must have result, front or top radiator doesn't really make a difference, the cpu/gpu could care less about 2°C, that'll change second to second with different loads.

If software isn't a concern, the Evga CLC 280 is a great, no nonsense aio that goes head to head with 360mm rads except at extreme top end capacity.

For software (regardless of quibbles about data usage etc) the nzxt Cam software is the best and most reliable for getting good results.

Aircoolers are not quieter than aios, often the opposite. That x61 ran far quieter at all load speeds when on silent mode than my cryorig R1 Ultimate in the same pc. Mainly due to software being able to tailor fan curves, which bios/motherboard will not do very well. Software can set up 0 surges, bios ramps fans easily with windows load changes.

Fans make noise. Kinda not fair to compare Noctua fans as an aircooler standard to older Corsair fans as a standard aio. If Noctua had an aio design the volume argument would go right out the window.

 

[BigObamus]

Thanks for all the help, I appreciate it. The only concern I have is, that depending on the mounting position I choose, I will either have to buy a 360mm or 280mm, as the 360mm doesnt fit at the top of the Obsidian 500D RGB. Looking at most tests and benchmarks, front mounting a 360mm AiO seems to be the best option, even though I don't understand the aerodynamics behind it.

 

[SgtScream]

If the 280mm fits better in the case go for that, especially if it saves you money to allocate towards other hardware. My friend has a 9700k and uses a front mounted 280mm aio and he wasn't even reaching 50c on a gaming load. I couldn't believe it. That's why i suggested to mount the rad on the top, because cpu temps might increase a little bit from that configuration, but the temps will still be ridiculously low and your graphics card will run cooler as a result from not having obstructed front intake fans. Again, The radiator's mounting position depends on the hardware components you're using. You can't compare a 7 year old i7 3770k/GTX 970 build with an i7 9700k/GTX 1080ti build and state temperature difference is negligable on all systems and hardware component combinations. The gtx 1080 ti costs significantly more and runs hotter than a gtx 970, so for that reason i'd mount the rad on the top and monitor your temps. The CPU will be water cooled, not the gpu.

 

[BigObamus]

The problem is not, that the 280mm fits the case better, but that the 360mm has no space at the top and only at the front. Comparing the prices of good 280mm and 360mm AiO there is a maximum of 20-30$ difference, so that's not the problem. Also i currently have 6 fans, so thinking about a push/pull config at the front. Many tests showed that there is basically no differnce between front and top mounting for the GPU, whilst the temps on the CPU drastically decreased witha front mount.

 

[geofelt]

One big advantage to a front mount is that if all the intake is filtered, your parts will stay cleaner.
Mounting elsewhere tends to draw in unfiltered air from other openings.

 

[BigObamus]

My case has very nice dust filters at all sides, so that should be no problem.

 

[geofelt]

My case has very nice dust filters at all sides, so that should be no problem.

That helps, but not all openings will be covered.
The rear I/O slots for example or case seams.

 

[BigObamus]

Would you guys suggest a H150i Pro or Kraken X72? My system (Case, Fans, RAM) is mostly Corsair, so I'm currently leaning towards the H150i Pro.

Also, having 6 fans at the front with a push/pull config, 2 outtakes at the top and 1 outtake at the rear, what will be the pressure inside the case?

 

[SgtScream]

The problem is not, that the 280mm fits the case better, but that the 360mm has no space at the top and only at the front. Comparing the prices of good 280mm and 360mm AiO there is a maximum of 20-30$ difference, so that's not the problem. Also i currently have 6 fans, so thinking about a push/pull config at the front. Many tests showed that there is basically no differnce between front and top mounting for the GPU, whilst the temps on the CPU drastically decreased witha front mount.

What hardware was being tested? Let me know how you make out. I don't have a gtx 970, but I do have a MSI gtx 1080 ti duke and it generates some serious heat.

 

[BigObamus]

The test was done with a 1070, not quite a 1080 ti, but close.

 

[SgtScream]

The test was done with a 1070, not quite a 1080 ti, but close.

Don't get me wrong, i'm not saying anyone is incorrect. Just test out different AIO placement configurations and find out the truth for yourself. There's no one solution for all systems. I look forward to hear about what you find out.

 

[BigObamus]

The problem is, if I buy a 360mm, I can only test it at the front, as only 280mm will fit at the top.

 

[SgtScream]

I'd say go for the 360mm rad for the i9 9900k, but with the i7 9700k the 280mm should be more than adequate for overclocking, let alone a gaming load.

 

[BigObamus]

But wouldn't a 360mm for a 9700k result in lower temperatures for the GPU as well?

 

[rubix_1011]

Not sure I'm following, unless this is strictly about ambient case air temp and if so, likely minimal if your overall case airflow remains good.