3090 + i9 9900k Watercooling

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Afternoon,

I've currently got a single loop setup cooling an i9 9900k, and a Zotac Trinity 3090 both at stock. I've got a 360/30mm and a 240/30mm radiator inside a Corsair 500D SE case handling this, and currently under load this keeps the CPU to between 60/70c and GPU under 50c and the coolant temp stabilises at around 40.

I'm wondering that if I were to update my case, would adding two or three thicker 360mm rads have any impact on the temperatures of the GPU/CPU?

Currently I'm using a Corsair XD5 pump, both rads are Corsair XR5, a Corsair XG7 GPU block and the XC7 CPU block.
 
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I doubt you would see much improvement tbh, I will be installing a 3090 onto a single loop with my 9900k soon so can let you know what my temps are, will be on a 360/40mm and 240/40mm
 
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I too am wondering if extra rad space would make a difference to CPU and GPU temps, Im running my i7 6950x at 4.2ghz playing MSFS2020 flying over London and I've got 57c on the cpu and 63c on the gpu with maxed out and the other not doing much at all.
Those temps are ok but I want to do something with the rig new case extra rad?? no need but I want to do something!
So would an extra 360 make any difference the two I have are the very slim (30mm?) Magicool ones.
 
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I tried overclocking mine previously on an AIO to 5 on all cores, but had to up the vcore more than I'd have liked to keep the temps below 95! I suspect I didn't win the silicon lottery with my chip.
 
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I'm hitting high 60s on Call of Duty Cold War on the CPU at stock, so not sure about OCing just yet. That's why I was curious if bigger rads would make a difference.
 
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Afternoon,

I've currently got a single loop setup cooling an i9 9900k, and a Zotac Trinity 3090 both at stock. I've got a 360/30mm and a 240/30mm radiator inside a Corsair 500D SE case handling this, and currently under load this keeps the CPU to between 60/70c and GPU under 50c and the coolant temp stabilises at around 40.

I'm wondering that if I were to update my case, would adding two or three thicker 360mm rads have any impact on the temperatures of the GPU/CPU?

Currently I'm using a Corsair XD5 pump, both rads are Corsair XR5, a Corsair XG7 GPU block and the XC7 CPU block.

With that kind of rad area, especially 30mm rads you're in the diminishing returns territory. You could get slight temp improvements but realistically you'd just be looking for fan speed reduction beyond your current setup.

If the GPU is under 50 then you're not going to see any throttling because of it and the CPU is just down to the block and voltage you have to cram through it to get your desired clocks.
 
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With that kind of rad area, especially 30mm rads you're in the diminishing returns territory. You could get slight temp improvements but realistically you'd just be looking for fan speed reduction beyond your current setup.

If the GPU is under 50 then you're not going to see any throttling because of it and the CPU is just down to the block and voltage you have to cram through it to get your desired clocks.

I meant to say the gpu is under 60. But I don’t think that changes your point in any way as it’s still way cooler on water than it was on air.
 
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If you're pushing past 50 degrees by any significant margin with something like a 30 series GPU then you will start to see a bit of clock throttling so if you're keen to completely negate that then a fat boy 360 to replace your 240 would do the job.

Alternatively, you could have a look at your current setup and see if you're willing to sacrifice for better thermal performance. What's the FPI of your current rads and what fans are you running at what RPM? Higher RPM could be enough to do the job if it's not too noisy, or you could potentially pick up some higher static pressure fans if you've got some high FPI rads etc.
 
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Temps seem high for a stock CPU. I would expect high 40's low 50's then up to high 60's when highly cooked.

This is my thoughts too. If I run prime95 or cinebench then it runs mid 60s at 100% load, which doesn’t seem that bad. It’s when the 3090 is under load too the temps of the cpu go up to the high figures, which is why I suspect my rads are potentially struggling a little.
 
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The rads aren't necessarily "struggling". The rads+fans have a negative effect on temps, the i9+3090 have a positive effect. When both cpu and gpu are generating the new stable water temp will cause both cpu and gpu to be hotter than if only one of them is generating heat.

The question is if the temps stabilise - even if the temps are not what you want - or if they keep going higher and higher until thermal throttiling occurs. If they keep going, then they're definitely inadequate and adding another rad or much more powerful fans would be required.

If they stabilise without causing throttling, does that cause an actual problem? If the system is stable and fast as you need, do the temps matter?

The temps in the first post don't look problematic to me.
 
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This is my thoughts too. If I run prime95 or cinebench then it runs mid 60s at 100% load, which doesn’t seem that bad. It’s when the 3090 is under load too the temps of the cpu go up to the high figures, which is why I suspect my rads are potentially struggling a little.

You should have enough rad area. Maybe try remounting the CPU block.
 
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It’s your water temps which are important so the 40 degrees your seeing is okayish, not great but not bad.

I have 9900k and at stock you will find motherboard can actually Chuck a lot of voltages into them at auto, combine with the in crappy general IHS and it’s a recipe that at stock with a demanding game you will see spikes even under water. Problem is not the loop, its the heat transfer from the a relatively small surfaced area CPU through crappy IHS design, through the TIM into the block.

If you want to reduce CPU temps I would look at dialling in manual voltage. The stock voltage curve account for the absolute bottom barrel CPUs, such as mine :( and even then pump excess voltage in. I would also ensure the mounting all looks okay.
 
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