New build now or wait for 5090?

I'm looking to replace my entire gaming rig and will swap out my RTX 3080 with a 5080 or 5090 when that comes out. Will the parts below be sufficient? I don't know if the PSU at 1200w is overkill or not, and I'm unsure if this motherboard will be good. The case will be a NZXT H6 Flow.

I've never built a PC before and will have a retailer help me do it. Thanks.