Oculus Rift requires constant 90FPS for it to work.You can't use it with the 980m simply because the resolution is 1080×1200 per eye which makes it like having dual monitor setup so there are pretty much no games that both work with the oculus rift and the 970m/980m can run at steady 90FPS at 2x almost 1080p resolution.If you actually want to use VR you need at least 2x980TI's to comfortably use it.
Overall VR is similar to 4k gaming in the fact that it is so cutting edge that the current technology barely keeps up with it.At 2x1080x1200 you are 2,592,000 pixels which would be fine if you didn't have a MINIMUM FPS number of 90.Maybe the 980m would be able to run some of the lightes games at that resolution but do you really want an Oculus Rift if you're going to be limited to garbage?
