Hi, apologies if this is a elementary question, or if I've posted it in the wrong place.

I'm trying customise a new audio workstation.

The motherboard at the moment is an Asus X99-S (Intel X99), which has "1 x PCIe 2.0 x4, and 5 x PCIe 3.0 x16"

I'm not sure what that actually means; I'm not sure about the difference between 2.0 and 3.0, nor the difference between x4 and x16. I've tried looking elsewhere online but the info I've found so far has only provoked more questions.

Anyway, I was wondering if the HDSPe AIO & the 2 expansion boards (AI4S-192 AIO and AO4S-192 AIO) would be compatible with that motherboard?

Any help that anybody might care to provide would be most appreciated.

Thanks.