I run a 9800x3d and a 4090 with an older 240mm AIO (2 fans) mounted on top and have no temp problems. Runs about 45 degrees at idle and 65-70 degrees running MSFS 2024.
You can never have too much cooling! Your sim temps are spot on however try running Prime95 for 30 minutes to see how your system holds up. My 9950x3d will max out at 90-92c (at 95c it will throttle but never goes that high) and with some calculations require 267w continuous (275w peak) as measured by cpu package power. Prime95 will stress your cpu & memory to the max so make sure you monitor your temps.
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I finally got Windows 11 installed and started testing my new PC (coming from the Mac world…) and I’m both relieved and impressed so far.
I have a 9800X3D and Samsung 9100 Pro 2TB both in a water loop (no GPU yet) that has 3x 420 radiators, and 9 Arctic P14 Max fans.
First run of Cinebench with completely stock BIOS settings, default Windows, etc, D5 Pump speed of about 70% or 4000 rpm 100 l/hr, and fans at about 50%… CPU didn’t go above 70 degrees.
Then when I set EXPO and PBO on, with a negative 20 curve offset (which I think is ‘undervolt’) and set to throttle at 85 degrees… Cinebench overall power draw was under 110 W and temps barely broke 60 degrees. I tried AIDA64, and a few others, with similar results.
The Aquacomputer software (Aquasuite) is pretty easy once you figure it out, and I could set both the pump and fan speeds based on a combination of coolant and component temps, so it ramps up under stress, but so far not needing to go over 70% pump speed.
The real test will be with a GPU, which is the main heat producer, but after months of stressing about this, I’m pretty thrilled with how it has turned out so far.
That’s great. For reference, my setup is:
7950X3D (be quiet! Deep Cool 4 aircooler)
3090 Ti (450W TDP) (liquid-cooled)
(1) 280mm top-mount radiator with 2x high static-pressure push fans.
Corsair XD5 pump/reservoir connected to the motherboard.
I have the pump set with a pretty mild speed curve, running at 30% up to around 50°C, ramping up to 50% when the GPU hits 60°, and 90% when it hits 80°C.
Both CPU and GPU stay right around 70°C during flight.
The GPU is slightly undervolted, and the CPU uses PBO2 Auto.
I do not use any additional cooling on my SSD’s or RAM, and their temps are fine - usually 35-45°C.
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When undervolting your cpu, I highly recommend the Corecycler utility. Here is a good article explaining it. Some additional recomendations if you use it:
- in step 7 use motherboard limits to get the best performance.
- in step 9, set the scalar to 10 which will allow the cpu to boost more aggressively
- in step 10, set the boost clock to 150
For the Corecycler itself, I’ve never needed to change any of the defaults
Also, setting your throttle at 85c is well below the thermal throttle limit of the 9800x3d at 95c (tjMax) so you are definitely leaving some performance on the table. Undervolting will lower the cpu temps which will allow more headroom for the cpu to safely boost higher and longer before it hits its default thermal throttle limit of 95c.
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Thanks for the tips
I did set PBO to use Motherboard defaults, and I added the 85 degree throttle to be safe.
I’m OK with that for now, mostly because running all the various benchmark and stress tests - Cinebench, AIDA64, Prime 95 - so far the maximum CPU temperature has hovered under 80 degrees, safely shy of the 85 throttle - which I’m really happy about.
That’s with CPU running 100%, about 5225 MHz sustained, the water pump at 80%, and fan curves at that CPU temp are about 75% I think, keeping it cool and fairly quiet.
I won’t push any further with customization until I’ve got a GPU and MSFS installed to see how it performs in its intended scenario first. Baby steps, as this is my first PC build, and water loop - the chances of me screwing up were greater than zero percent, but so far so good!
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Maybe someone smarter than me can chime on my belief that a CPU boost clock continues to increase until it reaches its thermal limit or voltage limit. IOW, if you set the thermal limit to 85°C you’re leaving a (small) amount of boost on the table.
I personally set mine to 89°C and only see it hit that temp under extreme load like the Prime95 Small FFT test.
So the question remains: If I never exceed 70°C in the sim, does setting a thermal limit even matter?
I have zero experience, but conceptually, if enabling PBO effectively removes the stock safety limits, I like the idea of having some upper limit for insurance, in case of a runaway heat event
In my case, if the CPU goes above 85 it’s likely the pump or fans have stopped, so I feel better having at least some guardrail there.
And if it turns out under maximum legitimate load, it still wants to go above 85, I’ll raise it like you have done, but still try to keep it under the CPU’s max of 95.
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I get that. I remember watching a video (JayzTwoCents, I think) where he talked about air-cooled vs. liquid cooled. One of the ppoints he made was that an air-cooler can react much more quickly (because of the specific heat of water) than a liquid cooler, which could be beneficial if you get a fast spike in CPU temp.
Another thing I remember reading somewhere that kind of blew my mind, is that a delidded CPU with no cooling would completely fry within seconds of turning the computer on.
Crazy how many kilocals the cooling system has to transfer.
I installed my first water cooler in my 9800X3D build earlier this year so everything was new to me. I was concerned about delayed response to CPU temp spikes. The solution that I read somewhere was to keep the pump running at - or close to - 100% regardless of CPU load and temperature. The fans can be controlled via the CPU temperature as normal. This means that, should the CPU temperature spike, you already have maximum cooling available. This gives the cooler fans some time to spool up in case the increase in CPU power/temperature is sustained for some time. Noise is typically generated by fans while the pump is quite quiet, so you do not have a lot of unnecessary noise with this strategy.
So far it has been working well for me.
Basically, water is denser (more thermal mass) and can absorb and move heat away from a component much faster and more efficiently than air.
Then as long as you have enough radiator surface area and airflow, its easy to keep the coolant temp low.
JayzTwoCents did a test recently showing that pump speed of about 80% resulted in lowest temps (under load).
I’ve set a pump curve from about 60 to 100% based on coolant temp (and will add in a factor that includes CPU and GPU temps).
I’ve set the fans to ramp up with CPU temp, from about 30% up to 100%.
I’m still experimenting, and it will change once a GPU is in the loop, but so far when CPU is in the Prime 95 torture test, pump at 80% and fans around 75 to 80, is keeping the CPU temp below 80 degrees.
Of course every loop is different. I went for the max I could fit: 3x 420mm rads. 2 are 45mm thick, and back one is 30mm but higher density fins. I chose Arctic P14 Max fans because they were inexpensive but have great static pressure for rads, which helps avoid having to run full speed.
I also used the largest volume reservoir that would (just) fit, to have coolant volume (about 1.5 L in the loop!). Last the fittings can add resistance, like the 90 angles and 2 quick disconnects I put in (already glad I did because I had to re-seat the M.2, and it was easier not having to drain everything.) But so far, luckily, it has all worked out better than I hoped.
Here is the rudimentary monitor I put together in Aquasuite, running the Prime 95 Blend, Large FFT and Hardest Small FFT tests. I think it’s largely the volume of coolant and large water block on the CPU keeping it cool, and I can probably tune the fans lower to be a bit quieter.
Yes, but if you’ve set the the throttle temp to only 85c, respectfully whats your point? All AMD ryzen cpu’s have a feature in that when the cpu hits tjMax limit (95c for the 9800x3d), it will throttle back to lower its temps to prevent any damage. If the chip is damaged by some unforeseen circumstance, it’s under warranty and AMD will replace it. The only reason to really keep the cpu below its tjMax limit is that the throttling reduces performance.