PHVM_BR

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?

2x32gb Ripjaws 5600MHz CL40.

Sunon. I change the heatsink assembly to install an RTX 4000 and was able to check. Both the original set and the new have Sunon fans.

Yes, it is the 90W VBIOS for Precision 7550. I even updated it. For comparison, on the graphics score in Time Spy: Quadro T2000 (60W): ~3620 Clock avg: ~1785MHz Quadro RTX4000 (80W): ~6930 Clock avg: ~1230MHz Quadro RTX4000 (90W): ~7530 Clock avg: ~1360MHz i7-9750H/T2000 vs i7-9750H/RTX 4000 (80W) vs i7-9750H/RTX 4000 (90W) vs i9-9980HK/RTX 4000 (90W) Result (3dmark.com) For now I'm using the Dell thermal paste that came applied to the new heatsink. When the new motherboard with i9 arrives I will exchange it for PTM 7950 so I should see some gain, although the thermals are under control in Time Spy (maximum: CPU 78°C and GPU 64°C).

The RTX 4000 and the compatible heatsink assembly arrived and I have already installed it to test. Everything perfect! I'm quite satisfied with the upgrade. The motherboard with i9-9880H hasn't arrived yet... I have some doubts: 1- Is it possible to adjust undervolt/overclock with MSI Afterburner on the Quadro RTX 4000 using a specific driver? 2- I'm going to update the VBIOS with the 90W version of the Precision 7550, but I would really like a 110W VBIOS like the 7740/7750. Has anyone gotten 110W on the RTX 4000 on a Precision 7540?

what is the TGP reported in the Nvidia control panel of the RTX 3500 Ada on the Precision 7680 originally?

I finally updated the BIOS from 1.24 to the latest available 1.29 and the undervolt is still unlocked. This confirms what I wrote some time ago, from an old BIOS update (1.08 or 1.09 if I'm not mistaken) the undervolt was blocked but just reset to factory default in the BIOS and it is released again.

Were you able to unlock the PL1 value in BIOS? A 7680 with PTM 7950, undervolt, 115W PL1 and 2x32gb 5600MHz Ripjaws would be what I was looking for...

What is the connection between XMP memory and undervolt?

I finally bought the motherboard with i9-9880H for my Precision 7540. I paid 300 USD for a new one in the original packaging. I also bought a “new” RTX 4000 open box also for 300$ and the appropriate set of heatsink with fans for another 50$. When it arrives and everything is in place I will post here the results and the comparison with the original specifications (i7-9750H and Quadro T2000).

This memory is compatible with Alienware M16/M18 and it appears that it activates the XMP profile automatically to run at 5600MHz CL40 with 2x32gb. I believe it can also work with Precision 7680/7780 since it is stated that these have the same compatibility with XMP memories in relation to the Alienware mentioned. Intel® XMP 3.0: Memory Profiles for Intel® Core™ Processors Just testing to be sure!