Question Are Corsair LL Case fans adequate?

Gee_Simpson

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Deciding what case fans to get. I'm considering RGB ones and the Corsair LL120/140 look the best. I've read they aren't great performers though, but do you need brilliant case fans or can you get away with using average ones? I have bought the LL140 and Silent Wings 3 but one of them will be getting sent back, I've not decided yet. I would prefer to use the LL140's but if they are poor then I may go the non RGB route.

I have the Fractal Design Meshify C case and I will be looking to overclock my i9 9900k to 5ghz all cores if possible. I've narrowed my choice of CPU cooler down to the NH-D15, NH-D15s or Dark Rock Pro 4. I'm considering Corsair RGB Pro RAM and I know it is only compatible with the NH-D15s, but again could use the non RGB LPX with either of the coolers.
 
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Karadjgne

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If you are going to all cores OC to 5GHz, none of those aircoolers will be up to the task. You'd be looking at a 250w output on a 250w cooler, so for all intents and purposes, they'd be roughly equivalent to a stock cooler at best. I'd recommend either a better 360mm AIO as they'll have wattage capacity upto @ 350w.

This could also solve your rgb fan issue, and be cheaper overall. ML360R, TT Rring/water 3.0 360, H150i Pro, Kraken X72, Celcius S36, Evga CLC360 are decent.
 

Karadjgne

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The top coolers are just enough for a 9900k at default stock settings, where only one core is hitting 5.0 at any given time, with a more average load of 4.7GHz.
The better the cooling, the better the power consumption. However, we were only able to record these large differences at package temperatures above 80°C, which then almost rise like an avalanche. This would dissuade us from air cooling, even if the Intel Core i9-9900K should not be overclocked any further. The 4.7 GHz all-core and a constant load are quite sufficient to make air cooling absurd.
That's from the Tom's review. All core 5GHz puts you at @ 250w. The top air coolers are @ 250w.

At decent OC settings for most hyperthreading cpus, you'll need to take TDP and multiply it by 2x - 2.5x to get a cooler capable of maintaing stress temps @ 70ish and gaming @ 55ish. So your 95w cpus generally do best on a cooler rated @ 200w. With the i9 and additional cores and extra threads, cooling capacity needs to be closer, if not beyond, 3x TDP.
The older i7's averaged around 80w ish, and the stock coolers that came with them were 110w. And insufficient to the task when loaded down, easily reaching temps of 90°C +.

At a 250w OC, seriously recommended to have a full custom loop, even a 280mm aio will see higher than normal temps.

It's a matter of capacity, and air coolers at that level are not enough.

And given that a 240mm is @ the same as big air, and your case restrictions, 360mm is the best option.
 

Gee_Simpson

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The top coolers are just enough for a 9900k at default stock settings, where only one core is hitting 5.0 at any given time, with a more average load of 4.7GHz.

That's from the Tom's review. All core 5GHz puts you at @ 250w. The top air coolers are @ 250w.

At decent OC settings for most hyperthreading cpus, you'll need to take TDP and multiply it by 2x - 2.5x to get a cooler capable of maintaing stress temps @ 70ish and gaming @ 55ish. So your 95w cpus generally do best on a cooler rated @ 200w. With the i9 and additional cores and extra threads, cooling capacity needs to be closer, if not beyond, 3x TDP.
The older i7's averaged around 80w ish, and the stock coolers that came with them were 110w. And insufficient to the task when loaded down, easily reaching temps of 90°C +.

At a 250w OC, seriously recommended to have a full custom loop, even a 280mm aio will see higher than normal temps.

It's a matter of capacity, and air coolers at that level are not enough.

And given that a 240mm is @ the same as big air, and your case restrictions, 360mm is the best option.

Hmm, maybe I shouldn't overclock then and stick with an air cooler although then again why go for a K chip and not overclock it? Doesn't make much sense to me?

So I'm guessing the advice from other people regarding overclocking a i9 9900k on air is wrong? There is multiple people on various sites saying they have overclocked to 5ghz on air, I'm again assuming these are the few lucky ones? View: https://www.reddit.com/r/intel/comments/c2f5sl/do_you_need_water_cooling_to_overclock_a_i9_9900k/

I'm a noob and have yet to build a PC for the first time. I have every part but I now may send back the Dark Rock Pro 4 based on what you have told me and go with a 360mm AIO. I've heard that they are unreliable (pump leaks etc) though, is this true? The Corsair H150i Pro looks the best to me but which one out of those you listed would you say is the best? I would probably still keep the LL140's for case intake fans as they look really cool. That would mean I wouldn't need the AIO to have RGB fans. I do like the fact that AIO's don't interfere or block the RGB RAM too.
 
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Karadjgne

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You are correct. Sort of. It's a matter of capacity. All fans being equal etc etc, if you put a 50w load on a hyper212, NH-D15, 120mm, 240mm, 280mm, 360mm you'll get roughly the exact same temps. Simply because that load is so far down the curve on any of those coolers that they all function the same. The difference starts showing up severely as you start approaching wattage limits

(ignore the numbers it's the graph curve that's important)
70w would be close to the middle on the 120mm/hyper212, farther left for the NH-D15/240mm, about ¼ for 280/360mm. Not very much difference at all.

A 140w load is different. As that's the rated TDP of the 120/hyper212, you'd be absolute far right, and the 280/360mm still haven't quite hit halfway (they'd be at the 10 on bottom). Temps on the 120/hyper212 would be at max.

At 250w, that's rated TDP of most 240mm/NH-D15, so same thing, at far right, but now the 280mm is about at the 30 and the 360mm is at the 20. Still not that great a difference. But to some ppl, that 5-10°C is a deal breaker.

You have a meshify C, so could do either, but the 280mm top out around 300w and the 360mm top out around 350w, and you are planning on a 250w OC. So you'd be covered, but you'll see higher overall temps with a 280mm under heavy loads.

Plus I think the 3x fans in front look better imho.
 

Gee_Simpson

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Thanks. That's good to know that I can go for either.

I'm a noob when it comes to this. If I put the AIO in the front of my case do I still need front intake case fans or do I only need exhaust case fans?
 
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Karadjgne

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That's the bonus to an aio. It comes with fans, some come with rgb fans. When you consider a decent rgb fan costs @ $30 each on average, $90 of a 360mm AIO is already accounted for. Ppl tend to forget additional case fan needs when saying air coolers are cheaper.

So with the aio, it's going to pull double duty. It can be exhaust or intake, depending on where you put it. To add insult to injury, it can also be used with existing fans, so if a case already has 3x rgb in front, and you add a 360mm rad, you can sandwich the rad between both sets of fans, this is called push-pull. One fan pushes air into the rad, other fan pulls that air through.

So how exactly you set it up is entirely up to you. You can keep the stock rad fans, swap them out, add to them, use push or pull or push-pull, your choice.
 

Gee_Simpson

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Thanks a lot. I think I'm going to go for the new Arctic Liquid Freezer II 280mm as it has amazing reviews, beating out even the 360mm NZXT Kraken x72. This one doesn't come with any RGB fans or pump head though. It only costs £75 vs a H115i Platinum which costs £144 but the Corsair comes with 2 RGB fans and RGB pump head. I don't particularly want any RGB intake case fans at the front because it lights up the front, showing a kind of spider leg like pattern in the Meshify C which I don't like the look of.

If I use both stock fractal fans (120mm) at the front and have the 280mm AIO at the front, will that be the equivalent of a 240mm + 280mm intake? Then I can keep the LL140 dual kit and use them as 2 exhausts, 1 at the back and 1 at the top. I would prefer the RGB fans there instead of the front for the reasons I mentioned. This would end up costing £135. Of course I could just go for the H115i with the RGB fans at the front as they aren't actually right at the front, they will be lighting the inside instead of the outside like front case fans would I think? Then I could use the stock fans as exhausts instead. £9 difference between the two setups.
 
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Karadjgne

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You won't be able to do that. Either way you plan. It's a matter of size and fit. There's not enough space behind the mesh to mount the fans exterior and rad interior, and you can't mount a 120mm fan to a 280mm rad. If you went 360mm, it'd work, as then you'd sandwich a 120mm between case slots and rad, and have the 2nd fan mounted in the rear of the rad.

So if opting for a 280mm, you'll be using just the aio supplied 140mm fans in front, and whichever fans you choose as exhaust, either the stock fans or the LL's. And still have the choice of push or pull, just not both.

Kinda gotta stick with 1 size choice with rad mounts, case mounts can be anything.

Since the option exists with the LL's at 140mm, you could use the aio fans in push, then rad, then LL's in pull, and use the 120mm's as exhaust, but that kinda defeats the purpose of buying/using rgb fans in the first place.

<---Fan Light <---Rad <---Fan-Case-Mesh <---Airflow path
 
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Gee_Simpson

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Ah, okay thanks. So the AIO fans will act as my intake and I just need to pick whichever for the exhaust. I could save some money and just use the supplied 2x 120mm fans as exhaust fans, although then again I would be without RGB. I could use the LL140 kit as my exhaust but then that would be neutral pressure, when I'm looking for positive. I could send the LL140 back and buy the LL120 triple fan kit but that would mean only using two of them as exhausts and leaving the 3rd one out. I'm pretty much set on the Arctic AIO, it looks to be one of the best AIO's out there. It's a shame it doesn't have any RGB at all and that the 360mm version isn't in stock but the 280mm version beat out the Kraken x72:
View: https://youtu.be/QOsmuRof5GQ
The Arctic II is only £75 so picking a RGB fan kit won't make it cost any more than a good 280mm/360mm AIO.
 

Karadjgne

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Don't worry about pressure. That constantly changes and is next to impossible to judge. At lower rpm, like idle, almost all cases are negative, it's not until you crank up the rpm high that you'll stand a chance of seeing positive, unless you have a serious imbalance, like 3x intakes and 1x exhaust. The difference between a 140mm and 120mm fan is usually quite negligible at anything less than maximum rpm. All you need worry about is flow, not so much pressure.
 
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Gee_Simpson

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Don't worry about pressure. That constantly changes and is next to impossible to judge. At lower rpm, like idle, almost all cases are negative, it's not until you crank up the rpm high that you'll stand a chance of seeing positive, unless you have a serious imbalance, like 3x intakes and 1x exhaust. The difference between a 140mm and 120mm fan is usually quite negligible at anything less than maximum rpm. All you need worry about is flow, not so much pressure.

Thanks for all your help :)

Now to build it, which I should be able to do on Wednesday or Thursday. I just hope it's not too tough!