Privet tebe toje!
I don't think R9 390X will be $350. Some leaker from BestBuy is posting $449 MSRP. I guess performance must be really close to NV's $499 980?
If we are going to use the logic that the OP will use his card 100% as a stop-gap, the priorities should be to spend as little as possible to get as close to a higher level pricing tier. At the current time frame that means comparing 290/290X/970 vs. 980. Spending less will allow the OP to save for $ towards the next gen HBM2 GPU, while reducing the level of depreciation come resale value. At that point a $220 R9 290, $270 R9 290X or $300 GTX970 meet the requirement.
$220 R9 290, $270 R9 270, $300 GTX970 or $350-440 R9 290 CF are the only reasonable options right now. I doubt R9 390/390X will change that. To really go up from here, one really needs a $650 single card flagship. Perhaps Fiji PRO will get closer to the 980Ti but it won't cost $350.
I'm happy to wait 2-3 weeks to see what happens. If 390x is close to 980 there may be price reductions for 980 and I'm hoping for a little price war :biggrin:. 390x at 389 is reasonable, especially if it's 8 gb and overclocks decently.