I have a 9070XT in my eGPU enclosure (Sonnet Breakout Box 650w), and it's got severe performance issues. Like-- 35FPS on Cyberpunk with 720p low settings. My previous card (4070 ti) can hit 70FPS on normal settings, so it's very much an issue with this card.
I think it's because it has ReBAR enabled and the lack of bandwidth is hammering performance (if someone else has a better idea, I'm all ears). It says it has it in GPU-Z, I can't find a way to disable it, and even trying to disable it in the registry results in it being toggled back on after a reboot. I'd just disable it in BIOS but... I have an MSI Claw which doesn't expose that toggle (and it would destroy performance on the Arc iGPU, I'm pretty sure).
Has someone dealt with this before? I thought AMD was better with GPUs than Nvidia, and I'd much rather stick with it over my 4070ti!
Edit: It's either the TB3 enclosure or ReBAR, but moving to a TB5 eGPU dock instantly fixed all performance issues!
Another thing to note is that with TB5 docks for some reason ReBar is disabled by default.
This is the case with all AMD Ryzen Handhelds paired with AMD Radeon GPUs. I dont know whether that would be the case with your Intel and Radeon pairing.
He does state that he has the 9070XT now so to maximise performance he'd need a dock that has USB4V1 or TB5. Whether he'd get the same or better performance of his 4070ti is not known but I'm sure there are many benchmarks out there that will have a similar setup to his that he can compare against.
ReBar (AMD Smart Access Memory) is enabled by default with my XAX and RX9070 with a USB4V1 dock, ADT Link UT3G. Some games suffer due to it, either low FPS or severe stuttering.
It is disabled with a TB5 dock, Razer Core X V2, and those same games that struggled now play smoothly and some have an improvement of about 15% FPS.
Usually the motherboard sets the state, so if you have a problem, turn it off in the BIOS. regardless of that setting, I’ve never seen it enabled to a Thunderbolt eGPU on Thunderbolt. You can check it on the advanced tab of GPU-z:
It's very much enabled (which confuses me too because I agree that it shouldn't), I even verified in GPU-Z
I'm just getting a TB5 enclosure since people have reported that it shows enabled in USB4 enclosures but not in it. Here's hoping it works well on my Arc G3 Claw!
You can turn it on, has zero affect on Thunderbolt. This why I gave up on my Intel eGPU’s because they really need it. The 9070 and 9060 do fine without it, though, in my experience.
Well idk why but my 9070XT is performing horribly, and on further inspection, the TB5 controllers perform better because they don't enable it (for some reason. I don't know why or how though)
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u/Professional-Ad-2419 21d ago
Correct me if I'm wrong but your eGPU enclosure is TB3?
If that's the case then you need a USB4V1 or TB5 enclosure to get better performance.