Precision 7540 & Precision 7740 owner's thread

[SvenC]

9 hours ago, Aaron44126 said:

 

Hyper-V blocks undervolting on both Windows 10 and Windows 11.  I believe that it is enabled by default in Windows 11 but not in Windows 10.  You can disable it by either removing it from "Turn Windows features on or off" or by passing a BCD boot parameter, but then you forego some features that rely on it, like VBS and WSL2.

I used Hyper-V on Windows 10 and was able to undervolt. I switched to Windows 11 about a year ago, so that might have changed. But Windows 10 versions from 2022 and older allowed undervolting with Hyper-V activated.

[PHVM_BR]

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?

[Aaron44126]

11 hours ago, PHVM_BR said:

Has anyone gotten 110W on the RTX 4000 on a Precision 7540?

 

I think @Ionising_Radiation did something similar with a RTX 5000 in a Precision 7530.  IIRC, Dell actually released a vBIOS upgrade package for the Precision 7X50 that ups the power limit.  You can download that, pull the vBIOS image out of the download package, and flash it yourself on an older system.

[PHVM_BR]

On 1/27/2024 at 10:34 AM, Aaron44126 said:

 

I think @Ionising_Radiation did something similar with a RTX 5000 in a Precision 7530.  IIRC, Dell actually released a vBIOS upgrade package for the Precision 7X50 that ups the power limit.  You can download that, pull the vBIOS image out of the download package, and flash it yourself on an older system.

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).

 

 

[PHVM_BR]

On 5/6/2023 at 6:12 PM, Kitje said:

Just curious, do you know what fan manufacturer your 7540 has?

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.

 

[TheQuentincc]

Hey @Aaron44126 @Ionising_Radiation, do you know if the 7730 P3200 heatsink will be compatible with the RTX 3000 from the 7740 ? 

Thanks

[Aaron44126]

5 hours ago, TheQuentincc said:

Hey @Aaron44126 @Ionising_Radiation, do you know if the 7730 P3200 heatsink will be compatible with the RTX 3000 from the 7740 ? 

Thanks

 

This was the case in the Precision 7530/7540 so I think that it is a decent bet.  I don't have specific recollection of anyone trying the same thing for 7730/7740.  I think you could get a pretty good feel by finding some good photos of the heatsink (eBay?) and stacking them to make sure it looks like the screw positions are the same.

[PHVM_BR]

On 1/26/2024 at 10:37 PM, PHVM_BR said:

I have some doubts:

1- Is it possible to adjust undervolt/overclock with MSI Afterburner on the Quadro RTX 4000 using a specific driver?

@win32asmguy @Ionising_Radiation

Hey guys, can anyone help?

[TheQuentincc]

On 2/2/2024 at 2:13 PM, Aaron44126 said:

 

This was the case in the Precision 7530/7540 so I think that it is a decent bet.  I don't have specific recollection of anyone trying the same thing for 7730/7740.  I think you could get a pretty good feel by finding some good photos of the heatsink (eBay?) and stacking them to make sure it looks like the screw positions are the same.

Turns out it's not the same heatsink, hole spacing are different between the P3200 and RTX3000...

[TheQuentincc]

So I finally modded the heatsink of my 7730 to fit the RTX3000 (I realised I didn't took any picture of it but you need 4 new holes...), since I had to replace the memory (Early Micron GDDR6 dying plague), I decided to upgrade the capacity, I now have 12GB working on the RTX3000.

FYI you need to replace the memory with Samsung (only) K4ZAF325BM-HC14 or K4ZAF325BM-HC16 (speed bin difference that doesn't matter here) as well as moving the strap resistor as attached. It works the same on RTX4000, you just can't upgrade the RTX 3000 to 16GB because the memory bus is not fully activated/working

[PHVM_BR]

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)

[TheQuentincc]

Is the RTX 3000 supposed to be limited at 80W on Precision 7740 ? mine is capped at 80W with vbios 90.06.39.00.64 (maybe it's the 7540 vbios ?), I thought it was supposed to be limited at 100~110W.

[PHVM_BR]

30 minutes ago, TheQuentincc said:

Is the RTX 3000 supposed to be limited at 80W on Precision 7740 ?

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.

[TheQuentincc]

alright, does the Precision 7750 RTX 3000 got higher TDP vbios ? maybe it's possible to use a 7750 vbios on 7740 ?

[PHVM_BR]

1 hour ago, TheQuentincc said:

alright, does the Precision 7750 RTX 3000 got higher TDP vbios ?

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

[Zeht]

I recently got a precision 7540 with i7-9850h and quadro rtx 3000. The machine works well, but there is a big issue with cpu throttling when the gpu is loaded, I tried several throttlestop settings but the issue persists. If I run any game or application that loads the gpu, after one minute or so the cpu starts throttling from 45W to ~20W. Then, after a few more seconds it throttles to ~5W!, reducing the clock to 800Mhz. This makes the laptop completely useless.

 

I checked my temps and they seem fine. I disabled BD PROCHOT in throttlestop, disabled Speedstep, tried several values for Speedshift and nothing seems to work. This issue only happens when the gpu is being used, if I stress the cpu it can hold 55W for several minutes without any problems, as soon as I load the gpu the throttle begins. Anyone else had this issue?, how can I fix it?. Btw, I'm running 1.25.0 bios version, which supports undervolting, but I don't mind losing it if updating the bios fixes the issue.

[PHVM_BR]

1 hour ago, Zeht said:

I recently got a precision 7540 with i7-9850h and quadro rtx 3000. The machine works well, but there is a big issue with cpu throttling when the gpu is loaded, I tried several throttlestop settings but the issue persists. If I run any game or application that loads the gpu, after one minute or so the cpu starts throttling from 45W to ~20W. Then, after a few more seconds it throttles to ~5W!, reducing the clock to 800Mhz. This makes the laptop completely useless.

 

I checked my temps and they seem fine. I disabled BD PROCHOT in throttlestop, disabled Speedstep, tried several values for Speedshift and nothing seems to work. This issue only happens when the gpu is being used, if I stress the cpu it can hold 55W for several minutes without any problems, as soon as I load the gpu the throttle begins. Anyone else had this issue?, how can I fix it?. Btw, I'm running 1.25.0 bios version, which supports undervolting, but I don't mind losing it if updating the bios fixes the issue.

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.

[Zeht]

11 minutes ago, PHVM_BR said:

Does this behavior occur when in ultra performance mode in Power Manager?

 

Yes, I just tried setting ultra performance, launched superposition benchmark and cpuz to stress cpu and gpu. The laptop maintains 45W for around 30 secs, then drops to 30W and after 30 more secs drops to 5W.

I got the igpu version of the laptop, then I added the quadro gpu alongside the compatible heatsink. The heatsink came with pre-applied thermal pads and paste, and while I don't think it's of the highest quality the temps seem fine. The moment the laptop begins to throttle my gpu is at around 70° and cpu at 90°, both far from the limit.

I really doubt the cpu vrm is overheating because if I stress the cpu alone it can maintain 45W indefinitely.

[PHVM_BR]

4 minutes ago, Zeht said:

I really doubt the cpu vrm is overheating because if I stress the cpu alone it can maintain 45W indefinitely.

45W for the CPU is very little for this machine.

You should be able to sustain 75W at ultra performance all day...

5 minutes ago, Zeht said:

The heatsink came with pre-applied thermal pads and paste, and while I don't think it's of the highest quality the temps seem fine.

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).

[Zeht]

13 minutes ago, PHVM_BR said:

45W for the CPU is very little for this machine.

You should be able to sustain 75W at ultra performance all day...

Yes, I just tested changing the PL1 at 75W and ran the throttlestop stress tool for some minutes, the max temp was 98° and it didn't power throttled. However, my issue starts whenever I use both cpu+gpu at the same time, that's why I lowered the cpu PL1 to 45W but that didn't seem to help.

 

Edit: I also upgraded to bios 1.26.1 which according to dell "improves system stability" but the issue persists.

[Aaron44126]

Is the behavior any different if you apply a power limit to the dGPU?

I think you can do this with the nvidia-smi command line tool by giving a value in watts.  (I.e. nvidia-smi --power-limit=50)

 

It could be related to NVIDIA dynamic boost, but the techniques I've messed with to work around that are for the opposite situation (GPU gets throttled in combined load)...

[PHVM_BR]

17 minutes ago, Zeht said:

However, my issue starts whenever I use both cpu+gpu at the same time

Are you running these tests with the original charger connected?

[Zeht]

11 minutes ago, Aaron44126 said:

Is the behavior any different if you apply a power limit to the dGPU?

I think you can do this with the nvidia-smi command line tool by giving a value in watts.  (I.e. nvidia-smi --power-limit=50)

 

I tried the command but it doesn't seem to work, I get the following error:

"Changing power management limit is not supported for GPU: 00000000:01:00.0.
Treating as warning and moving on.
All done."

 

11 minutes ago, PHVM_BR said:

Are you running these tests with the charger connected?

Yes, in fact I don't have the battery plugged, but I don't think that's the issue. It may be related to how dell throttles power using an embedded controller, which apparently can fail after some time causing it to trigger a power throttle even if the temperatures are ok.

If I limit the cpu to 25W then I can run superposition+cpuz for 5 minutes without any issues. I tried 30W and after 2 minutes it throttled down to 5W, despite the gpu being 72°c and cpu 78°c

[PHVM_BR]

3 minutes ago, Zeht said:

in fact I don't have the battery plugged

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

[Aaron44126]

I can't claim for sure that this is the culprit, but I have also seen these laptops act weird without the battery.

 

Are you using 180W or 240W power adapter?  Do you have a 240W that you could try?