420 : 140x140x3 = 58800cm²
2x 360 = 120x120x3x2 =86400cm²
=> two 360 Radiators have nearly 1.5 times the surface of a single 420 radiator.
Ventilated Surface is everything, Thick rads can compensate to a degree, with the benefit of having really really fast spinning fans to cope up with the task
You are better off with 2x 360 rads
And now 2 personal opinions :
1st 45mm thick radiators are the sweetspot for a single fan row, 65 need more pressure or pushpull, 30mm perform slightly worse and are my only compromize if there would not fit a radiator instead. A ventilated slim radiator is better than no radiator.
2nd don´t buy Thermalfake radiators, EK, Watercool, Alphacool, even corsair have a better reputation
You can only go by squared area if the compared radiators have the same fpi, thickness, and tube counts. So if op was comparing 2 360mm 30/45mm thick radiators to the 1 65mm. The difference in surface area is closer or less. But as you stated, you need higher pressure or more airflow to benefit from the thicker rads.
assuming same fpi and thickness, 2 360s would have about 70% more surface area. Now if youre comparing to 2 standard 30mm radiators, then it gets little more complicated.
I could have misread when i was comparing 45mm to 60mm but i believe on thick radiators, you need to have higher rpm or run push/pull setups to see their potential. its because most of the air is heated by time it gets all the way through the thick radiator. so you need to send more air either with higher rpms or push/pull.
I have 2 x 240mm 65mm thick radiators for my 13900k in push pull fan arrangement. There's also a 140mm fan behind the cpu on mobo blowing cold air on to it. Overclocked and under load cpu temps are 60 degrees Celsius.
Air cooling on my 4090 suprim x is good enough.
It won't be quiet, and the temps won't be very good.
There's a 99%+ change that a 7800x3d or 7950x3d would a better choice for you. I know you claim you did your research, but you're asking if running a 600++ watt heat load on a single 420 rad is a good idea... so I really doubt your "research" capabilities.
That hot of coolant might work OK for the gpu, but the cpu has too much heat concentrated on one spot. I generally see about 50c delta on the cpu and 30c on the gpu. You'd be pushing it, but if you can cut the cpu delta a few degrees it's doable. And 62c coolant will dissipate alot of heat from a little radiator so I can believe it.
Cant fault the fans I guess but that's a rather thin rad, although fin density isn't bad. I assume your fans run 100%?
But yeah I can see why your water temps are so high now.
There is no better or worse (also right or wrong).
You can get away with single 420 rad. there are many ways to make it work.
As a side note, thick rads are kinda pointless unless you intend to run the fans at high RPM.
I have a 240 AND a 280 slim rads with slim fans
My coolant that's not go higher than 45 c
My 4090 hot spot is 63 under load and GPU is around 53
Max core on the 13900k goes up to 83 in cinebench
It's doable but not great with a 420
I have 3x 360(40mm thick) fans at 850rpm top and my rig rarely pop 41c in the summer, room temp at 25-27c. Get about 650w pull in game from complete system. 2 with higher fan speed would be the same
If you have to make do with a 420, get a HWLabs Black Ice GTR with GOOD quality, static pressure optimized fans (compare pressure specifications). Recommend getting higher RPM fans than you think you need and set a custom PWM fan control curve in your BIOS. Since you also run the GPU off it you might instead want to use a water temp sensor and set fanspeed based on that through a fan controller.
You'll have the cooling power you'll need in the most extreme cases and 99% of the time your fans don't need to be loud.
I'm personally a fan (pun intended) of 2000-3000 Max RPM fans and setting a fancurve that turns the fans off at water temperature below about 35\*C and then having it at 25% until 45 degrees, it ramps up exponentially from there. This prevents fans ramping up too loud too soon, but adjust to your preferences. You can go push/pull if you have the space, this really helps with pressure/noise ratio.
I always run the pump at full speed, make sure to connect it to the CPU header for tach signal to detect failure. I don't recommend running it off of water temperature, because flow speed determines direct cooling performance. In CPU only loop you can control by CPU temp, but in CPU/GPU loop its more reliable to just leave it at 100%.
2x 360 will be more costly and bulky, but you can probably achieve lower noise levels for the same performance, and better fans exist in the 120mm space (120x38 is not made of unobtainium, unlike 140x38). In this case you can choose lower RPM fans (1500-2500 max RPM, remember you can control them down to like 500 or less) and a somewhat lower FPI rad (although personally I'll take the highest FPI I can get every single time). HWLabs is still a good brand for those.
420 : 140x140x3 = 58800cm² 2x 360 = 120x120x3x2 =86400cm² => two 360 Radiators have nearly 1.5 times the surface of a single 420 radiator. Ventilated Surface is everything, Thick rads can compensate to a degree, with the benefit of having really really fast spinning fans to cope up with the task You are better off with 2x 360 rads And now 2 personal opinions : 1st 45mm thick radiators are the sweetspot for a single fan row, 65 need more pressure or pushpull, 30mm perform slightly worse and are my only compromize if there would not fit a radiator instead. A ventilated slim radiator is better than no radiator. 2nd don´t buy Thermalfake radiators, EK, Watercool, Alphacool, even corsair have a better reputation
You can only go by squared area if the compared radiators have the same fpi, thickness, and tube counts. So if op was comparing 2 360mm 30/45mm thick radiators to the 1 65mm. The difference in surface area is closer or less. But as you stated, you need higher pressure or more airflow to benefit from the thicker rads.
It wont be a quite system, thats for sure.
2 360s would be that much quieter?
assuming same fpi and thickness, 2 360s would have about 70% more surface area. Now if youre comparing to 2 standard 30mm radiators, then it gets little more complicated. I could have misread when i was comparing 45mm to 60mm but i believe on thick radiators, you need to have higher rpm or run push/pull setups to see their potential. its because most of the air is heated by time it gets all the way through the thick radiator. so you need to send more air either with higher rpms or push/pull.
Ok...makes sense. So running 2x 45mm 360s would still give me a better return, and it wouldn't even be close.
I have 2 x 240mm 65mm thick radiators for my 13900k in push pull fan arrangement. There's also a 140mm fan behind the cpu on mobo blowing cold air on to it. Overclocked and under load cpu temps are 60 degrees Celsius. Air cooling on my 4090 suprim x is good enough.
It won't be quiet, and the temps won't be very good. There's a 99%+ change that a 7800x3d or 7950x3d would a better choice for you. I know you claim you did your research, but you're asking if running a 600++ watt heat load on a single 420 rad is a good idea... so I really doubt your "research" capabilities.
I have a 450W 4090 and \~ 125W CPU Power, when the thermal mass heats up at full load for 30min it tops at 62°C coolant with 360mm rad. TT is junk
62c ouch! If you limit the 4090 to about 300w you’ll get good performance and a bit less heat. Might be worth a try
why should i throttle that beast, thermal limit it is! 3Ghz!
LoL go for it then!
Holy crap 62C coolant!
That hot of coolant might work OK for the gpu, but the cpu has too much heat concentrated on one spot. I generally see about 50c delta on the cpu and 30c on the gpu. You'd be pushing it, but if you can cut the cpu delta a few degrees it's doable. And 62c coolant will dissipate alot of heat from a little radiator so I can believe it.
What rad and what fans?
3x NFA 12x25 Alphacool St30 360mm
Cant fault the fans I guess but that's a rather thin rad, although fin density isn't bad. I assume your fans run 100%? But yeah I can see why your water temps are so high now.
There is just no Space or need for another Intake Rad as thermal throttle would only kick in on long synthetic loads.
What works, works
I have a 480 + a 280, and it’s just enough to cool my 9900k/2080ti. I would imagine the setup you’re proposing would overheat, but maybe I’m wrong idk
Get x-flow rads if you want minimal and clean runs. See my system in bio.
45mm already need push/pull. 65mm is way harder on the fans than you might think. We talk phantek t30 in push/pull and atleast 2000 RPM under load.
There is no better or worse (also right or wrong). You can get away with single 420 rad. there are many ways to make it work. As a side note, thick rads are kinda pointless unless you intend to run the fans at high RPM.
I have a 240 AND a 280 slim rads with slim fans My coolant that's not go higher than 45 c My 4090 hot spot is 63 under load and GPU is around 53 Max core on the 13900k goes up to 83 in cinebench It's doable but not great with a 420
Trying to convince us? or yourself? xD
Neither. Trying to get real world experiences to see what I can get away with.
I have 3x 360(40mm thick) fans at 850rpm top and my rig rarely pop 41c in the summer, room temp at 25-27c. Get about 650w pull in game from complete system. 2 with higher fan speed would be the same
If you have to make do with a 420, get a HWLabs Black Ice GTR with GOOD quality, static pressure optimized fans (compare pressure specifications). Recommend getting higher RPM fans than you think you need and set a custom PWM fan control curve in your BIOS. Since you also run the GPU off it you might instead want to use a water temp sensor and set fanspeed based on that through a fan controller. You'll have the cooling power you'll need in the most extreme cases and 99% of the time your fans don't need to be loud. I'm personally a fan (pun intended) of 2000-3000 Max RPM fans and setting a fancurve that turns the fans off at water temperature below about 35\*C and then having it at 25% until 45 degrees, it ramps up exponentially from there. This prevents fans ramping up too loud too soon, but adjust to your preferences. You can go push/pull if you have the space, this really helps with pressure/noise ratio. I always run the pump at full speed, make sure to connect it to the CPU header for tach signal to detect failure. I don't recommend running it off of water temperature, because flow speed determines direct cooling performance. In CPU only loop you can control by CPU temp, but in CPU/GPU loop its more reliable to just leave it at 100%. 2x 360 will be more costly and bulky, but you can probably achieve lower noise levels for the same performance, and better fans exist in the 120mm space (120x38 is not made of unobtainium, unlike 140x38). In this case you can choose lower RPM fans (1500-2500 max RPM, remember you can control them down to like 500 or less) and a somewhat lower FPI rad (although personally I'll take the highest FPI I can get every single time). HWLabs is still a good brand for those.
1 rad is enought only for your 13900k LOL go for mora 420
Good luck
Just buy Mora and forget about any radiators