I've recently bought a second GPU for Vegas Pro (Rendering) and for better overall performance while gaming.
- i7-4790k OC 4,7GHz watercooled
- 32GB DDR3 2133MHz
- a bunch of SSDs and HDDs
- 980 Strix OC
- my new RX580 Nitro+
- Windows 7 Pro x64
I figured I could run two seperate GPUs individually for each monitor. That way my second monitor shouldn't cause dropped framerate while gaming. Also I wanted a card for OpenCL (Vegas Pro), so I picked up an RX580.
I've noticed very strange dips in performance though. Sometimes everything is fine. Both run at their respective framerates. Suddenly my main monitor (980) drops by about 20 fps for no reason and stays that way. When I play a Youtube video on my secondary monitor and play certain games, I get 15-20 fps. What could be the issue here?
The drivers? AMD drivers and NVIDIA drivers not understanding each other? The CPU bottlenecking because it has to talk with both drivers simultaneously? A driver that's not fully worked out for the RX 580 yet?
I'm curious for your opinions.
Edit01: One thing I also should mention: I'm running an Asus Z97-WS board. That particular MB has 16 PCIe lanes + 16 via some extender chip. Might that be an issue? Is it using those lanes for the GPU and hence the performance issues?