You’re probably only getting 54w even with no dGPU because of the cooling. I did the PTM7950 sandwich mod which allows me to get significantly better heat transfer for better cooling.
What temps are you getting when you run the benchmark?
I haven’t done the sandwich mod, just regular framework cooler with PTM7950 or PTM7958 or whatever it is.
I am hitting 100C on one core, but only just barely between frames. See a graph of the hwinfo data during Cinebench R23 run in my post above Uneven CPU thermals! - #1400 by Micah_Lindstrom
It’s probably throttling. Before I did the mod my CPU would hit the same temps with some cores in the high 80s. The only difference being th wattage would be around 48-49.
Great entry! Also planning to do the exact same thing.
I was just thinking, since you didn’t exactly get what you wanted, did you use pure copper?
Even tiny amounts of alloying have a massive impact on thermal/electrical conductivity.
For example, CW024A is a common copper alloy with 99,9% copper and 0.015 - 0.04% Phosphorus and has a thermal conductivity of 340 W/m°C. While at 99,99% pure copper will have a thermal conductivity of around 391 W/m°C or roughly 15% better.
Could that explain the results?
The lower results are because of 50w power limit on the CPU from one of the newer BIOS updates, not from thermals. In this post here, I got a much higher score from disabling the dGPU, which allowed the CPU to consume as much power as it wanted, and got a slightly higher score by about 11%. Even then, when the CPU was allowed to use as much power as it wanted the temps stayed around the 90-95c after the power stabilized. I’m also not sure what type of copper it was, or its purity, but here’s the eBay link from where I got them. Heatsink Copper Pad Shim 20mmx20mm 0.3mm/0.5mm/0.8mm/1mm/1.2mm/1.5mm 2Pcs | eBay
I can only dream of such figures for now! Thanks for the link, I’m going to have to look.
Well, I’ve finally caved. I just ordered a new heat sink and all the parts to do the PTM sandwich mod.
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which parts did you order? I would like to give it a try as well but paranoid that I will break something else and then I void my warranty and out of a machine for weeks. Do share your experience and steps once you get it done 
Thanks!
I got the heatsink part from the framework store along with 3 spare ptm pads for the die-side.
PTM pad from LTT (for the shim/heatsink side): PTM7950 Phase Change Thermal Pad – LTTStore
Copper Shim from Amazon: Amazon.com: Copper Pad Shim Thermal Assortment Kit, IC Chipset GPU CPU Thermal Heatsink Copper Pad Shim 20 x 20 x 0.8mm, Pack of 20 : Electronics
And some higher grit sandpaper that goes higher than what I already have: High Precision Polishing Sanding Wet/Dry Abrasive Sandpaper Sheets -Grit 3000 5000 7000 Germany - Amazon.com
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What’s wrong with your original heat sink?
I’m not sure if anything is wrong with it, it’s probably fine. I just don’t want to risk messing up my only one, and my CPU easily hits 100c so there might be something up with it, idk. Getting another seemed a reasonable way to solve both those problems with P2W.
One thing I’m trying to understand is why not just remove the shim entirely? Does the heatsink collide with something undesirable before reaching the die this way?
Mounting pressure.
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Ok, so what I’m hearing is that if I’m careful not to overtighten… the shim is unnecessary.
The one that is soldered on, you can remove it (you bought a spare for this reason right?). Test it without it first. I have great results with the copper shim added. ymmv.
I cannot remember how long I did the modification, but since, I never needed to service it, it’s been operating quietly ever since.
Yeah, that’s why I got the spare (which arrives today!).
Thanks for sharing.
During my development of the shim mod i tested it without any shim and it was really bad, not as bad as run off liquid metal, but bad. The shim or even a slightly bigger shim help alot and overtightening is not an issue, if you screw down to the block its done you cant overtighten just strip the threads.
I soldered my shim to the vaporchamber and i am still running more than 58w steady Load and 78w peaks with the ptm installed over 1 year ago.
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Good to know! That saves me a lot of time, thanks! How did you solder it on? I checked the thread for details on that but couldn’t find any, and am interested in doing this myself.
Update: nevermind, found it! Search results are in the opposite order I assumed they were.
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Well, I’ve gone and done the PTM sandwhich mod, and oh my it worked! My CPU when from being hard-locked to 100c to running at 85c average with a maximum of 90c (in BF6). Interestingly, this only translated into +200 points on cinebench and not much more, but I’ve not yet let the ptm go through it’s burn in cycles. It’s looking more and more like the throttling issue I’m running into with BF6 may be the dGPU getting hot itself after all, so I may look to take what I’ve learned here and apply it to the dGPU somehow (RX 7700s).
I kinda destroyed some of the pink thermal pads though, so I gooped thermal putty all over those VRM’s. Hopefully that doesn’t fail me down the line.
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Nice job! The 200 points is probably the CPU watt limit of 50w on 180w charger and 54w on 240w charger. What temps are you getting on your 7700s? I’ve had the thermal paste pump out twice over the last I’d say 6-8 months which has led the dGPU getting high 90C. Simply replacing the thermal paste with Arctic MX-6 brings it down to about 78C hotspot. It doesn’t require the PTM sandwich mod because the heatsink is actually properly designed.
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