Question High GPU usage causes internet to slow

[mribah78]

MSI Z790 Gaming Pro Wifi
i7-14700K
4070 Super (12 GB)
Rosewill Hive PSU (1000W)
64 GB RAM
3 x m.2 (2 TB, 4 TB, 4 TB)
2 RGB Fans on CPU cooler, 1 non-RGB case fan
KVM switch for 2 monitors, keyboard and mouse
Open case/test-bench/mining rig style case.

Sorry, I wasn't sure where to post this, but the common denominator in my problem is 100% GPU usage so here we go. And also sorry this is long, but there are a lot of moving parts and I can't make sense of it.

When my GPU is under a heavy load (80%+), my internet speed drops significantly, by over 40MB/s.

I wasn't having this problem until I did two things at the same time. 1) I started using a KVM switch for my 2 monitors so I could use my other PC at the same time with the same monitors and mouse/keyboard, 2) I moved my external GPU (3 foot pcie 4.0x16 riser cable) from the front of my case near the RAM to the back of my case near the I/O panel.

I've been learning to use deepfacelab for the past couple of weeks, which puts my GPU at 85-100% according to the Task Manager, and since I moved the GPU and started using the KVM switch, sometimes my internet speed drops to 0B/s while the GPU is under a heavy load. Sometimes it gets to 10MB/s, sometimes 20MB/s, but as soon as I shut down deepfacelab and my GPU usage drops down my internet speed goes up to 50-70MB/s. I've tried testing the speed with downloading large files from multiple sources on multiple browsers, and with online internet speed tests. I've tried putting the GPU under strain with stress test programs instead of deepfacelab, all combinations sometimes produce a slowdown in internet speed when the GPU is at high use.

I saw on reddit that the GPU frequency can interfere with the Wi-Fi, and sometimes when I move the GPU around helps, but sometimes it doesn't. What helped the most was I plugged in my KVM switch into a power strip instead of having it powered by the PC, but that still only gets me to around 20MB/s while the GPU is running instead of 60MB/s while the GPU is idle. The KVM switch needs to be plugged into the PC's Display Port and USB with a split "Y" cable, I couldn't move that USB to a power strip. Sometimes unplugging the riser cable and reseating it helps, or maybe it is just that I have rebooted the PC.

So what the hell is going on here? if it is a frequency thing, why does it only sometimes help when I move the GPU around, and why is the speed still slow when I put it back where I had it weeks ago when my internet was fine? Could it be that the power consumption of the GPU isn't leaving enough for the Wi-Fi even though I have a 1000 watt PSU? I think this may be possible, since having the KVM switch draw power from an outlet instead of the PC means that I get about 10MB/s speeds instead of 0B/s.

I've tried going into Device Manager and unchecking "Allow the computer to turn off this device to save power" for all of the Network adapters (Intel(R) Wi-Fi 6E AX211 160MHz, Realtek Gaming 2.5GbE Family Controller, and Realtek PCIe GbE family Controller), even though I'm not really sure which I should be focusing on or if that would have any affect. I've also tried to download "Open Hardware Monitor" and "HWI 772", but I can't figure out how to determine my power usage in them.

Thanks for reading, any ideas?

 

[Lutfij]

Open case/test-bench/mining rig style case.
Might want to pass on an image at the very least. In your instance, have you tried aiming a fan around the general area of the GPU to help generate some airflow with ambient air?

BIOS for your motherboard?

 

[mribah78]

Open case/test-bench/mining rig style case.
Might want to pass on an image at the very least. In your instance, have you tried aiming a fan around the general area of the GPU to help generate some airflow with ambient air?

BIOS for your motherboard?

Hi thanks for the reply

In System Information :
BIOS Version/Date: American Megatrends International, LLC. 1.20, 9/6/2023
SMBIOS Version: 3.6
Embedded Controller Version: 255.255
BIOS Mode: UEFI

In Command Prompt (wmic bios get smbiosbiosversion) it says: 1.20. Not sure why they are different.

My GPU is sitting outside of the case, it is on a 3ft long riser cable, I did have it near some of the case fans but that didn't seem to help. The internet slows down though even when the GPU is cold to the touch, like I'll turn the PC on for the first time that day, start a speed test (70MB/s), then start a stress test for the GPU, and then do another speed test and I'll get 40MB/s, and I can touch the GPU and it is still cold.

 

[jacksloves]

Hi thanks for the reply

In System Information :
BIOS Version/Date: American Megatrends International, LLC. 1.20, 9/6/2023
SMBIOS Version: 3.6
Embedded Controller Version: 255.255
BIOS Mode: UEFI

In Command Prompt (wmic bios get smbiosbiosversion) it says: 1.20. Not sure why they are different.

My GPU is sitting outside of the case, it is on a 3ft long riser cable, I did have it near some of the case fans but that didn't seem to help. The internet slows down though even when the GPU is cold to the touch, like I'll turn the PC on for the first time that day, start a speed test (70MB/s), then start a stress test for the GPU, and then do another speed test and I'll get 40MB/s, and I can touch the GPU and it is still cold.

Hey did you ever figure out the issue? I have the same motherboard and have a similar issue. If I run anything computationally intensive even a little, such as installing a new program or launching a game, my WIFI quality drops a ton. If it's on the 5Ghz band, I just lose internet connection and if it's on the 2.4Ghz band, the wifi quality just drops a ton, slower speeds.