Laggy Desktop when plugged into eGPU
Hi all! I have a Thinkpad X1 extreme first gen with a mantiz saturn pro egpu enclosing a RTX 2070S. Under windows, my external displays feel extremely laggy. As in, I feel like the windows are operating at about 5fps max, but the mouse is moving at a smooth 60fps. This is most noticeable when scrolling or typing, and using it like this is pretty much unbearable. When I unplug the egpu, I have no problems using my built in laptop display. Restarting sometimes fixes the problem, but about 70% of the time the problem is still present at bootup, or returns within minutes. The only "fix" I have found is running the command "taskkill /f /im dwm.exe" which occasionally fixes the issue, but lately has been working less and less often. I went so far as to reinstall windows to no avail. I've tried using DDU to uninstall and reinstall the drivers also to no avail.
I also have a dual boot with Ubuntu, and that exhibits no issues whatsoever, so I suspect this to be a windows issue. I'm running the latest 432 Nvidia drivers.
Does anyone have any ideas?
A fix for a similar, common error that resembles what you are describing is to open device manager and disable your iGPU, most commonly Intel UHD, under the display adapter's tab.
@ningauble77, So, I've just noticed this same scenario as well. I expected that I would have to disable my dGPU on a late 2019 Blade 17 Pro (2080 Max-Q) to run an external Core X Chroma (which just happens to fit a Zotac Trinity 3090 perfectly). I figured that was no big deal. However I noticed today while working, that my desktop was REALLY laggy, and regularly would "lose" my left mouse button, as the entire desktop would not respond to left-clicks at all, Though it would respond to right-clicks, somehow. So I would pull up Task Manager, and that would get my left-click functionality back for a brief time.
So, this is all on a multi-monitor setup; Blade 17 Pro, TB3 to Razer Core X Chrome (RTX 3090), which is connected to a 43 in LG 43UD79-B 4K monitor (via DP), and via HDMI to a small 15 inch 1920 x 1080 monitor that I use for travel.
Once I disabled BOTH the Intel iGPU and the 2080-Max-Q, now my desktop has zero lag and all is good. However that's not an ideal situation, as I need to remember to enable at least one of the built-in Display Adapters prior to shutting the laptop down and disconnecting it.
My next experiment will be to leave the Intel iGPU enabled, but instead to "disconnect" the primary laptop display in Windows Display settings section, and run it that way. I have a sneaking suspicion that may be part of what causes the issue as well, as the system should be able to handle the two displays connected to the RTX 3090 just fine.
With my old (much older) Blade 14 setup + Core v1 (GTX 1080Ti), I ran the laptop with the lid closed most of the time and I never had any desktop lag issues, ever. I'll leave the lid open for cooling, but keep the display off to see if that helps.
Okay, I've done some more experimenting with this, and here are my current findings. I've re-enabled my Intel iGPU, but have disabled (or rather, 'disconnected') my laptop's primary display and have made the 4K monitor my Main Display under Windows Display settings. So far it has been running for several hours without any "desktop lag" at all. Next experiment will be to re-enable the NVidia 2080 Max-Q dGPU, and see what the results are from there as well.
On another note, I realize that the RTX 3090 in an eGPU (or heck, even in a desktop machine) is overkill, and not the best bang for the financial buck, given that this Zotac card is $2K (CAD) and most RTX 3080 cards are running in the $1100 range (again, CAD). Perhaps it was more money than brains, but it was most certainly more money than patience, as even pre-ordering an RTX 3080 card was looking at a 4-6 week wait, OR it entailed hanging around one of my local stores in the hopes that a 3070 or 3080 card came into stock.
Round two of the experiment, and I've (briefly) re-enabled the RTX-2080 Max-Q in the laptop. Desktop lag has re-appeared almost instantly, so definitely not a proper solution at this time. Which makes sense, so I can understand that. Looks like the prime solution is to Disable the dGPU when the eGPU is connected, and to Disconnect the laptop main display when connected to my eGPU and dual-monitor setup as well.
Okay, so the instant I disabled the on-board dGPU, all desktop lag disappeared. I know Razer had their own GPU Switcher app back in the GTX 1060 / Blade 14 days, so I wonder if that tool still functions at all?
@, And I can confirm that the Razer GPU Switcher app (from 2016) does nothing at all to mitigate the situation. As expected, but I figured it was worth the try.
There might be multiple things causing this. One thing I've noticed on the 2020 Razer Blade Stealth, and the 2018 Macbook Pro 13 I used to have, is I would get constant desktop lag when I closed the lid on the internal display, but that signing out and signing back in fixed it. This doesn't fix the periodic hitching I get running 3dmark and superposition, which require actually disabling both the Intel and nvidia gpus. Using the 2019 Macbook Pro 16 I replaced the 2018 macbook with, I never had this issue at all, but its intel graphics are completely absent in bootcamp.
@ningauble77, So, I've now been running for several hours with my laptop display enabled, Intel iGPU enabled, and 2080 MaxQ dGPU disabled while running the eGPU with RTX 3090. No desktop lag that I've been able to detect for several hours now, and I just ran through several instances of 3DMark to run some basic benchmarks. 6368 in Time Spy Extreme 4K, 9638 in Fire Strike Ultra 4K, and 19520 in Fire Strike (FHD). Obviously the Fire Strike (FHD) score is low, but that's to be expected given the performance loss over TB3, and the fact that the RTX 3090 is really tailored to 4K gaming.
For comparison, my 5+ year old Corsair One desktop with an Intel Core i7 7700K and GTX 1080Ti pulls 20328 in Fire Strike (FHD), but only 6732 in Fire Strike Ultra 4K and 3944 in Time Spy Extreme 4K.
The laptop alone running with the 2080 Max-Q pulls 18124 in Fire Strike (FHD) on the internal display.
Now that I think I have this platform all sorted out, I think I'm pretty happy with the performance, as long as I don't add up the price tags.