High load on RTX Ada, low on Intel Arc

kfriedberg

Hi all,

It's time for another of those threads of "what's wrong with this computer?"

With this laptop (and its twin, bought at the same time), when using the Nvidia RTX Ada (new name for Quadro) graphics and showing stages, load in Isadora starts higher than expected, and if a show is run for long enough load increases until Isadora stutters out into a full freeze, requiring a computer restart to clear the condition. The interesting part is I've discovered that load is way lower if I force Isadora onto the Intel Arc graphics. No longer term tests on that yet, but levels are low enough that I'm not worried about a crash.

Specs for the laptop are: Dell Mobile Precision 3591, Win 11, Ultra 9 185H, 2TB NVMe SSD, 64GB DDR5, NVIDIA RTX 2000 Ada Generation 8 GB

Just starting from an empty file, on showing stages on the RTX, load stabilizes at about 17%, compared to 1% on Intel. In the show I've been given, at the point where things really take off, load will swing back and forth between ~30% and 70% on RTX, but not go above 4% on Arc. Windows task manager and resource monitor show neither graphics card going above 10%.

I've tried switching out the graphics driver, going with the one the comes down from Windows Update, the latest from Dell, and the latest stable as well as beta from Nvidia.

Other than finding a different computer to test on, any ideas on what I should try next?

mark_m

@kfriedberg

I presume you've used the NVidia Control panel (or Quadro equivalent) to tell the system to use the Ada card for Isadora?
Are you able to disable the Intel Arc card at all? In the BIOS perhaps? Wondering if that might make a difference...

kfriedberg

@mark_m

Newer Windows ignores the Nvidia control and uses this instead:
https://www.windowslatest.com/...
No problem using that, it's how I've switched between Arc and RTX to see the differences, and Task Manager shows Isadora going to GPU 0 or 1 depending on how it's set.

No option in the BIOS to disable either graphics card. I remember seeing that in past models, but double checking against the service manual, that's not a thing in this one.

DusX

@kfriedberg

Try ensuring that no displays are connect the outputs that feed directly to the Intel gpu. Only use connections that are direct to the RTX. This should help eliminate transfers between the two.

kfriedberg

@dusx

Not an option with a laptop, unfortunately. The ports are those that come with the laptop, and they're shared.

DusX

@kfriedberg

My laptop for example has two sets of ports. One on the left connects directly with the NVidia card, while the one on the back of my machine connect thru the intel card.
If you look at the PhysX section of your NVidia control panel, you can see which physical ports connect and how (some laptops allow the re-assigning of these via GPU settings, for instance my machine allows for 3 modes, active power saving that switches between gpus, low power usage which doesn't use the dedicated gpu at all, and only dedicated gpu where the intel gpu isn't used ever.)

So the PhysX section of the control panel will indicate if any connected display is running through the intel gpu or not, and will indicate which port facilitates the connection (these only update for me after I make a change and reboot my system). Unfortunately not all PCs offer the same variety of setups.

kfriedberg

@dusx

Many adjustments and reboots later, and still no luck. I've found the diagram of connections, and whether I connect to the HDMI or USB-C ports, they all show as connected to the Intel Arc, with only PhysX pointing to the Nvidia RTX2000. I've played with all the performance/quality options I could find in the Nvidia panel, the Intel Arc panel, and Windows power/graphics settings, and all the connections still go to the Arc card.

I tried disabling the Arc card in Device Manager. Windows still knew that the Nvidia card existed, but refused to send anything to it, disabled outputs except for the laptop screen, and thought that everything was showing on a Basic Display Adapter.

Any further ideas? This has me stumped.

mark_m

@kfriedberg

have you talked to Dell support? In the past I have found them to be knowledgeable when I had issues (not related to yours) with a Precision mobile workstation.

kfriedberg

@mark_m

Not yet, but a good idea after I do some more testing. My latest switch to the Game Ready series of drivers seems to have stabilized load at under 30%, but that's still well above the Arc's 4%. If I have time before vacation I'll compare to a desktop with a GeForce/UHD combo, otherwise more results to come in a few weeks.

DusX

@kfriedberg said:

30%

It may be that there is some delivery delay going thru the arc 2 the Nvidia gpu. However a heavy patch that maxes the Intel arc only processing may be easily handled using the arc 2 Nvidia path. I would suggest running some heavy test files where the Intel processing maxes out, then see how high that goes on the Nvidia.