(This is a cross-post from LTT Forums – nobody tried to answer there)
Hey all! This is my first post in the Level1 forums, and glad to finally be here. I hope you all can help me.
TL;DR: I need to split my PCIe x16 into 2x x16 in order to install another GPU. Any suggestions for a (preferably PCIe Gen4-compatible) riser/splitter? I’m OK with buying an X570 board if necessary.
Before I ask my question, here is my setup (as it pertains to my question):
OS: Linux
Motherboard: Gigabyte X470 Gaming 7 Wifi
GPU: Geforce 1660 Ti
Case: Phanteks Enthoo Luxe (full tower with plenty of clearance for oddball cards)
1x LSI 9300-8i HBA (requires 8x PCIe 3.0)
Just a little background before I ask my real question: I’ve used LInux as a primary OS for every machine I’ve owned since 2007. That being said, a lot of work has gone into getting things just they way I like them, with many cron tasks and other things that I simply can’t get anything done without. So, I have to effectively schedule time to play certain games around the daily work that happens on my machine. If I switch into Windows to play games I can’t play with Wine/Proton, then I can’t get any real work done in the background. And, building another rig is out of the question at the moment.
At one point in time, before I got my HBA, I had two GPU’s in the machine (the 1660 Ti and a 1050 Ti) and successfully got Windows running in a GPU-accelerated virtual machine using Looking Glass. It was tough to set up, but it was worth it! However, since I got my HBA, I no longer have any place I can sanely put another GPU on my board when I can finally get my hands on one. This leaves in a bit of pickle: I’d like to get virtualization set up again so I can do things like gaming in Windows without having to interrupt my quality of life and daily workflow too much.
For a bit I was pretty convinced that I was going to basically have to upgrade this system to a Threadripper just to get the lanes needed to plug all these cards in. However, I neglected to consider the possibility of splitting ports. I’ve never done anything like this before and I’d like some advice and recommendations if anybody has experience in this area. Effectively, I’d like to split my PCIe x16 slot into 2x PCIe x16 slots. I don’t think this board supports bifurcation, but that might be a non-issue after considering the rest of the equation. The way I figure it, even with an active splitter of some kind, I’d still be effectively halving the bandwidth of each card making them effectively 2x PCIe 8x on my PCIe Gen3 board. That’s probably usable, but obviously not ideal.
If I could get ahold of a PCIe Gen4 board and some kind of PCIe Gen4 splitter, then halving the bus speed for each card effectively brings it to Gen3 speeds which is perfectly fine and what I would consider my ideal solution in this situation. I am completly OK with buying an X570 board if required and I am open to suggestions (I prefer Gigabyte and I need 4x DIMM slots that can run at 3600 Mhz fully populated).
Does anybody know of a PCIe Gen4 1x x16 to 2x x16 splitter that could be used in some way to allow me to install an extra GPU? I’ve tried doing my due diligence here, but I’m pretty unfamiliar with this particular area of hardware and my Google-Fu has failed me spectacularly. If anybody could lead me in the right direction, I would be very grateful!
Note: I did find one card that looks like it may work (Supermicro RSC-G2F-A66-X1), but it’s only Gen3 and I hesitate to even try it if there’s potentially a better solution available.