XPS 8940, Better 3rd party cooler

Hi @SteveK318 thanks for the sharing. Will get the Noctua 92mm fans next round.

@PauRoNL  Does the fan at bottom help cool down the GPU card?

Hi @SteveK318 do you know if Dell cooler has the 125w one? Cause I only saw 95w so far but manual show there is 125w...

Refer to page 40-43 of manual

https://dl.dell.com/topicspdf/optiplex-7080-desktop_owners-manual5_en-us.pdf

Ah.... Summer !! good information !!

@Gerrard Loo - I don't know if that's the same one used in the k variant cpu's or not. maybe someone more knowledgeable on that topic can help you out. 

Might be a noob question but does anyone know if it's possible or worth it to fit a PCIE fan/fan bracket above the graphics card? Even with my Noctua fans the single intake fan on the dell version of the RTX 2060 isn't quite cutting it for cooling during long render times and VR stuff.

@Gambit_man - glad to here you went forward with installing the Noctua NH-U9S cooler ! And really glad that the results exceeded your expectations ! I'm just curious since I put a fair amount of time in trying different mounting methods, which way you went ? Did you go with the conventional method of screws and washers, or did you use set screws (grub screws) and the Noctua thumb nuts included with the cooler ?

@SteveK318  I went with the 3m x 16mm screws with 3m washers which was the method I had seen described most often in the various threads and which worked well. I did later see your posts about also being able to use the grub screws and supplied Noctua thumb nuts, but by then I had already ordered the screws and washers from Amazon at the same time I ordered the cooler.

With hindsight I can see that the alternative method is probably even easier as you can screw the grub screws into the 4 mobo holes then pop the black spacers over the top of those so they stay held in place while you put the spacers on. With the screw and washer method you have to place the black spacers over the mobo holes and kind of hope they stay still while you carefully place the brackets on top of them ready for screwing. I did have to fiddle around slightly to get everything to line up but not a real issue.   

@LjChesla do you mean something like this? If so, you'd likely get better results with this installed UNDER the GPU so that it blows air into the GPU fans (if your GPU is a blower style that exhausts heat at the back of the PC).

Don't expect spectacular results though, as you are still limited by the quality of the GPU fans themselves, as well as by the quality of the way in which the heatsink was mounted on the GPU. And from the pictures and videos I've seen online, Dell's OEM manufacturer (likely MSI or Foxconn) haven't really gone for a high-quality installation or thermal paste application. I've seen pictures of plastic labels not having been removed from the underside of the heatsink, which is supposed to make metal-to-metal contact with the GPU memory shield, I've seen a mess of thermal paste that did more harm than good and so on.

If you want a significant difference in temps, there are a few methods, but they will void your GPU warranty as they all involve removing parts of the heatsink.

1. De-shroud it: remove the plastic that covers parts of the heatsink, remove the dell fans, install larger high-quality fans (e.g. Noctua) directly on the heatsink.
   
   
2. Re-paste it: remove the entire heatsink off the card, clean the GPU really well of the messy thermal paste job, remove plastic stickers off the metal surfaces if needed, apply high-quality thermal paste to both GPU itself as well as the part of the heatsink that contacts the memory shield. Re-install everything.
   
   
3. Combine options 1 & 2 for even better thermal gains
   
   
4. The most drastic option: remove the entire heatsink and discard it / make it a paper weight. Install a GPU waterblock and go with liquid cooling (might as well do the CPU too at the same time).

I am planning to eventually go with option 2, or maybe 1&2. Not yet, but maybe by the end of the year.

I have received my XPS 8940 with i9 11900K. After confirming that the all components are working good, I replaced the original tiny case fan with a 120mm Arctic P12 PWM PST CO (very tight fit with squeezing it to the back wall) and attached another identical one to the upper front area. I should say it is louder than I expected (at least for my taste)! But I can definitely feel the airflow by hand in front of the grill. Haven't stressed the pc yet so I don't know how well they will keep the cpu cool. But no load temperature is around 28C within the 22.5 C environment. Maybe tweaking with the rpm may help to reduce the noise. Is there any good way to do it?

Minor typo in my last post.  What I meant to say was.... you can screw the grub screws into the 4 mobo holes then pop the black spacers over the top of those so they stay held in place while you put the Noctua BRACKETS on. 

@bertro514 - wow, that's crazy - they actually left the plastic on ? I haven't had any trouble with my card, so I think I'm good for now. But if I win the lottery (which I don't play) I might go for it and tear my GPU apart and re-paste it... other than that, not at this time !! And by the way, warranty shmoranty  .  At this point who cares !!

What’s an easy way to put a reasonable load on the VRM to heat it up (nothing extreme)?  I plan to install the 612F7 (knockoff) heatsink tomorrow, but would like to do a before and after test to see how much temp difference the heatsink makes.

@Richmond Dan if you want to really stress the VRM, first download ThrottleStop and remove the turbo limits on the CPU so that it sustains a long term/indefinite boost with high power consumption.

To do that, first open the FIVR window in ThrottleStop and check the "Disable and lock Turbo power limits" box, then reboot, then open ThrottleStop again, go into the TPL window, set both PL1 and PL2 values to 250 and slide both time sliders all the way to max.

Then run a stress test / benchmark: either Cinebench all-core, or Prime 95 (pick the "Small FFTs" option and set it to run on all threads), or even the stress test included with ThrottleStop (the "TS Bench" button). When that's running on all cores, monitor the power draw in ThrottleStop. Make sure it doesn't go back down to 65W after about 30 seconds (which would mean that the Turbo Boost is still being limited). If all goes well, the CPU should boost to a significant wattage (my 10900F hovered around 200-205W) and the VRM temp should go up. Keep that running for 20-30 minutes and see how far up it goes. Ideally, the heatsink keeps it under 100. (VRMs have a higher thermal cutoff point than the CPU. It can go up to 115-120 before it forces a shutdown AFAIK. The actual components themselves can take up to 130-140 without malfunctioning).