PHVM_BR

Try lowering it to -210mV in core while keeping the -126mV in cache. This should allow the CPU to increase clock speed during Cinebench. It makes a big difference to move the air intake away from the table top. A simple laptop stand solves the problem. The Precisions have the power limits locked in the EC, so if selecting Ultra Performance in the power manager does not increase PL1 you are limited to 60W. On the Precision 7540 this limit is 75W. You can try to increase PL1 and check Lock MMIO to confirm. Your Speedshift is at 84 which is not ideal for pure processor performance. If it's Windows 11, select performance mode and Speedshift goes to 63 and this makes a small difference. I personally don't use High Performance mode (Speedshift 0) by checking the option in the main Throttlestop window.

If the clock is at 3.7GHz at full load at 90°C, your problem is not thermal limitation but power limit. In Dell Power Manager are there different performance profiles? On the Precision 7540 there is the Ultra Performance option that increases the power limit and fan rotation, making it possible to achieve more performance. Post a screenshot of the Throttlestop FIVR window here. With the undervolt you mentioned you should be reaching the maximum performance of this Xeon. With PTM 7950 you will get another level in the performance / temperature ratio. I have a Precision that had an i7-9750H, similar to the Xeon in your laptop, and with PTM 7950 I could run Cinebench R23 at maximum performance (4.0GHz on all cores) without undervolt consuming ~100W at ~95°C with the fans at maximum. With -125mV in the cache and -210mV in the core, consumption decreased to ~60W under the same conditions and the temperature was ~78°C with the fans at 75%. You will not need to change the thermal pads because if you buy an RTX 3000 you will need a new heatsink assembly and the thermal pads are already applied. In my experience these machines do not require replacement thermal pads to obtain maximum hardware performance.

If I'm not mistaken, this Xeon can go up to 4.1GHz on all cores at full load. Limited to 3.7GHz at full load it is certainly suffering from throttling due to insufficient power limit or thermal throttling. If your undervolt is actually applied it is probably limited to 3.7GHz due to the thermal limit. With a good thermal compound and undervolt you will get the full performance of this CPU easily.

In full load multicore like Cinebench, the i7-10850H's default maximum clock rate is 4.4GHz. 5.1GHz is only reached in lighter loads that only require a single core. You don't obtain benefits above 4.0GHz in Cinebench due to thermal limitation. Without throttling and maintaining 4.4GHz on all cores you would have a proportionally better score (~10%). I don't have a 7550, but I do have a 7540 and mine can sustain ~100W in medium duration loads (up to 2 or 3 minutes) with PTM 7950 and a laptop stand to move the air intake away from the table top. Around 90W is possible for long periods without thermal limitation. It's strange that your 7550 with PTM 7950 has a lower thermal headroom than my 7540 because all the reports I've seen state that the 7550 has slightly better cooling capacity than its predecessor (maybe ~10 or 15%)... Maybe it's a bad application or the lack of good contact between the heatsink and the die. I would check the temperature difference between the cores during a full load (Cinebench). Generally, 8th/9th/10th Intel CPUs with 6 cores have a difference of around 5 to 7°C between the hottest and least hot cores when there is a good application of the thermal compound. A difference of up to 10°C is valid, more than that could mean your application failed. This applies to full loads. On my 7540 I also discovered that KryoSheet can deliver more than PTM 7950 (if there is good heatsink contact). With KryoSheet I can sustain energy consumption around 15% more than with PTM 7950 (~107W for long term heavy loads). You can also enable undervolt with a simple BIOS edit and thus achieve higher clocks with the same current power consumption.

I have access to an AIO with i7-1355U and even this CPU with only 2P-cores can achieve multicore performance similar to the i9-9980HK with undervolt and overclock of 4.4GHz all cores (~12k in Cinebench R23) and consuming about half of the power (~60W).

The Precision 7540 here is like an old man in top shape: RTX 4000 Max-Q 90W (Precision 7550 VBIOS): https://www.3dmark.com/spy/52615614 Quadro T2000 (60W GDDR5): https://www.3dmark.com/spy/52510073

From the 12th generation onwards Intel removed the possibility of undervolt from H series CPUs. For laptops only HK and HX CPUs can have their voltage adjusted. Try PTM 7950, in addition to excellent performance it should correct small imperfections in the heatsink contact.

What is the TGP that the Nvidia control panel reports? Performance will depend on TGP. I believe that on the Precision 3581 it should be limited to ~50W.

What exactly does this? I unlocked it out of curiosity and my i9-9980HK clocks were stuck at 800MHz. To unlock undervolt and increase ratios this is not necessary, what does it do?

BIOS defaults return the configuration of the installed BIOS. If the installed version is anything above 1.7.0 this will block the undervolt. Factory Defaults returns the original factory BIOS configuration. If the original BIOS is 1.7.0 or lower this option will unlock the undervolt. If it is 1.8.2 or higher, this option will block undervolt if it is unlocked.

It's not a 5540, but I tried charging via USB-C on the Precision 7540 with a 100W GaN charger from Ugreen and it's not supported. I thought it was a problem with both USB-C ports, but I tried charging via the USB-C port on the Dell P2723QE monitor (USB-C Hub 90W) and it worked perfectly. It's probably some deliberate blocking by Dell only being compatible with their devices.

Have you tried restoring factory settings in BIOS? If your laptop left the factory with BIOS 1.7 or lower this is enough to restore the possibility of undervolt. Otherwise, the option is to edit the variables (very simple).

RTX 2000 Ada = RTX 4060

I purchased a 240W Alienware SFF (GaN) power adapter and it works great on the Precision 7540. As before with the original 180W power adapter at full CPU + GPU cross-load, the i9-9980HK remained at ~60W and the RTX 4000 at ~90W but now there is no more battery drain. The system works by consuming ~150W from the CPU and GPU simultaneously, around ~180/190W in total, without discharging and without thermal throttling. Impressive! I'm very pleased with the new investment (i9 / RTX 4000 / 240W adapter).

The problem is definitely the lack of battery. I did the test without battery running AIDA64 CPU test + Heaven. With BD PROCHOT the CPU worked inconsistently, varying between ~15 and 30W while the GPU also fluctuated, unable to maintain a constant ~90W. While the tests were running, the BD PRO alert flashed red constantly in the ThrottleStop main window. By unchecking BD PROCHOT, the GPU started to work apparently normally, while the CPU continued to oscillate strongly, but with higher power levels, between ~15 and 60W, mainly between ~20 and 50W. This time the POWER alert flashed red constantly.

Tomorrow I'll try to test and post the results here. See the screenshot of the ~14 minute test I did simultaneously using the AIDA64 CPU Stress + Heaven still with i7-9750H / RTX 4000 (90W VBIOS) / original Dell thermal paste from the new heatsink / no undervolt:

I seriously believe it's the lack of battery. Many systems, especially with dGPU, limit heavy usage when there is no battery connected. In ultra performance, your laptop should maintain at least 45W on the CPU simultaneously with the GPU. In fact, I believe that the default behavior of this machine is for the CPU power to fluctuate between 60 and 45W (depending on temperatures) while the GPU consumes its 80W. My original system had an i7-9750H and Quadro T2000 and the behavior at full load CPU + GPU was the i7 varying between 60 and 75W while the GPU maintained 60W (its maximum TGP). In the case of RTX 3000 or higher, this CPU limit is lowered as the GPU consumes more (80W).

I believe we discovered the culprit: it's the absence of the battery!

Are you running these tests with the original charger connected?

45W for the CPU is very little for this machine. You should be able to sustain 75W at ultra performance all day... Yes, I never had any limitations like that even with thermal paste and original pads (the thermal pads I use are the original ones from the new heatsink assembly I bought for the RTX 4000).

Does this behavior occur when in ultra performance mode in Power Manager? My 7540 can constantly maintain 60W (~90/92°C) on the CPU (i9-9980HK) if I force it by blocking the power limit with Throttlestop in parallel with 90W (~77/79°C) on the GPU (RTX 4000), but at this level the battery will be drained heavily even with the 180W charger. If I limit the CPU to 50W the battery drain does not occur and the temperatures decrease. I believe you need new thermal paste for the CPU/GPU and probably new thermal pads for the VRMs as well. If your system came with BIOS 1.7.0 or lower, you can update to any version and your undervolt will remain unlocked. If the original BIOS is 1.8.2 or higher and you can undervolt it will remain unlocked even if you update to the latest version, you just cannot restore factory defaults or BIOS defaults.

No, the max of the RTX 3000 mobile is 80W.

RTX 3000 mobile has a max TGP of 80W and that's exactly it on both the 7540 and 7740. For RTX 4000/5000 the TGP is 80W on the 7540 and 110W on the 7740.

I had bought a new motherboard with i9-9880H, but it never arrived... There was a problem with the order at customs. I then ordered a new one with i9-9980HK which arrived last week. After installation I started tuning and refining the new system (from i7-9750H/T2000 to i9-9980HK/RTX 4000 Max-Q) with some discoveries: - Systems that left the factory with BIOS 1.7 or older have the undervolt unlocked even when installing the latest BIOS, just return the factory defaults (BIOS). This was the case with my original system with i7, but this new one came from the factory with BIOS 1.11.2 and this trick is not possible because restoring factory defaults returns the original BIOS defaults. The option for undervolting are to either downgrade to BIOS 1.7 (or older), reset the BIOS default and then you can update to the latest BIOS that the undervolt will remain. - The PL1 and PL2 power limits (75/107W on the i9 and 75/90W on the i7) are locked, but sporadically, without understanding the pattern, I was able to unlock them by checking the MMIO lock box in ThrottleStop. I discovered that going into sleep with the values changed and lock MMIO marked when the system returns the defined values are maintained. I was surprised by the performance the Precision 7540 can squeeze out of this i9. I was even able to maintain an overclock of 200MHz on the all core clock (4.2GHz > 4.4GHz). Above that, thermal throttling becomes a problem and is not worth it in this chassis. Maybe with LM and better luck in the silicon lottery the i9 can maintain 4.5GHz on all cores... 1- Original power (75/107W) / without undervolt 2- Power limit unlocked / without undervolt 3- Original power / undervolt 4- Power limit unlocked / undervolt / 4,2GHz (default) 5- Power limit unlocked / undervolt / 4,4GHz (slight thermal throttling at the very end of the test)

@win32asmguy @Ionising_Radiation Hey guys, can anyone help?