TL;DR; Repaste could make a big difference whether or not you're throttling at 80C or 100C. Results below.
Disclaimer: Don't try this at home unless you're comfortable with computer assembly/disassembly and able to delicately handle very thin fan wires with very dainty connectors.
Excellent repaste results with Arctic MX-4 (with an 8850H):
- Instructions here https://imgur.com/a/Blvpjd0
- WAY too much paste was on there from factory, far beyond the edges of the chips and piled up on the chips and the heatpipes and onto the plastic film. Ridiculous. Maybe they had too many units that were short on paste and they started globbing it on there at the factory, I don't know. If it's not automated metering/dispensing at the factory (I'm a Computer Engineer and I've been to an electronics factory in China twice, and not everything is automated) then there's a definitely possibility of a variation between factory workers. If there is too little or too much paste either situation will hurt performance and spike your temps.
- Spread a very thin film of MX-4 on both the CPU and GPU first using a plastic spreader stick. Then placed a drop of MX-4 in the middle of each chip and screwed down according to the linked instructions. Then waited a couple minutes, undid it all to check there was the right amount (complete coverage to the edge of the chip with very little extra outside of that). Then I did it again from scratch (completely cleaned it) and used the same technique using the correct amount.
- The following results are with XTU settings of:
- Core Voltage Offset: -0.125V
- Cache Voltage Offset: -0.125V
- Graphics Voltage Offset: -0.040V
- Multipliers per Active Cores maxed out at 47x/46x/46x/45x/45x/44x
- Turbo Boost: 45W (this was the default)
- Turbo Boost Short: 75W for 28 seconds (this was the default)
Also BIOS was updated to 1.17, and mesh was removed from vents.
w/ Virtualization in BIOS Off:
BEFORE -> AFTER
Max temp: 100C -> 96C
XTU: 1638 -> 1684
Cinebench R15 CPU: 1003 -> 1222
Cinebench OpenGL: 127.21 fps -> 133.95 fps
(Note: After repaste it is now Power Throttling instead of Thermal Throttling. Great! That is a good thing.)
w/Virtualization in BIOS On:
BEFORE -> AFTER
Max temp: 80C -> 80C
XTU: 1458 -> 1526
Cinebench R15 CPU: 841 -> 964
Cinebench OpenGL: 113.85 fps -> 123.69 fps
(Note: Still Thermal Throttling at 80C of course but MUCH better benchmarks!)
I believe the results speak for themselves, the repaste was worth it in this situation. Also the idle temp is as low as 49C now.
As a side note, after repaste I think I'm okay with the system throttling at 80C now with Virtualization ON in the BIOS... the temps are lower which is probably better for the processor, the fan comes on less, and the performance is now pretty good. As another side note, this 8850H processor is really meant for a bigger case and better cooling than the X1E to squeeze the most performance out of it, but hey, I'm stuck with it now and I'm finally okay with everything (after going through the BIOS 1.15 Discrete Graphics brick affair) knowing that I've done just about as much as I can do (apart from getting a laptop cooling pad which is arriving tomorrow which might help even more).
Honestly this system is engineered pretty well for a powerful processor given the space constraints, I just wish more care was taken with the thermal paste at the factory so there wouldn't be so many people having "Your Mileage May Vary" issues on these forums.