Agree, a 970 is low-end for VR. It will run fine but with lower detail possible. You're likely seeing the Oculus Asynchronous TimeWarp function working overtime and not being able to cope. If you move from side to side, or move about with the debug camera, it will be pretty bad. Just turning your head will be okay for the most part.
If ATW is struggling, and having to make up two or even three frames in between each real frame the 970 is outputting, then the textures will appear to get torn up.
You'll be seeing 90fps all the ttime in VR, but some of the frames will be synthetic, not rendered by your 3D card but interpolated from previous frames (ATW, and ASW if you've enabled it in the registry). The actual ED frame rate will likely be much lower than 90 except in space away from planets and stations. ATW is good to insert odd frames, but can really reduce image quality even though it keeps the frame rate you see at 90fps.
If it didn't, you'd probably feel sick pretty soon. :x I'm on a 1080GTX and in/near stations I'm not seeing 90fps, ever.
Try using the Oculus Debug Tool - start it before starting ED. Set the visible Performance HUD to "App Render Timings" and you'll see how many frames your 970 is actually dropping. it will show you the real frame rate the 970 is pumping out, the time it takes to render a single frame (you only have 11ms to render each frame, so render times over 11ms means you're pushing way too much detail)
What sort of detail settings, in-game super-sampling (probably 1.0x) and debug tool pixel density (if any) are you using?
You can drop blur, depth of field entirely, and bloom to off or medium, and ambient occlusion to off or low. Shadows to low or medium. You'll see an improvement.
On a 970 I wouldn't expect you to be able to use any pixel densities over 1.0x in the debug tool.
Also, try the in-game supersampling set to 0.85... you might find that improves your frame rate a bit too.
