Exactly right t0yz. I have an i7-920 from 2008 that is roughly equivalent to an i3-4330 in terms of sheer computing power.
http://www.cpubenchmark.net/compare.php?cmp[]=834&cmp[]=2025
My single thread performance is about half the performance of the 4330, but CDPR's optimization of all cores allows me to stay at a smooth 60FPS at 1080p. The game pushes my GTX 970 harder than it does the CPU. Meanwhile, shitty unoptimized games running on single thread make me consider upgrading my CPU.
I know exactly what you mean, I have an FX 8350/GTX 970. The crap that runs on 1-2 cores (like MMOs for example, WoW, Wildstar...) runs quite badly. The GPU drops as low as 20% utilization with huge framerate impact, like, I can go to 10 fps in a huge raid in WoW just because of the CPU core being unable to process so much info fast enough, while in same zone I can get 140 fps if no NPCs/players around doign stuff, putting stress on the CPU.
Having Witcher 3 being able to ramp up on all CPU cores as the situation demands it (cities with lots of NPCs) is a blessing, I can maintain 45+ fps with almost everything on Ultra@1080p.
That would explain why my psu just died last week
I have i5 4690K and gtx 970
Well, you should try and get a certified PSU, try for at least Silver, although there are some cheap-ish Gold PSUs around. If both your GPU and CPU do so much work at the same time like it happens in W3, it will put a lot of stress on the PSU and if they're cheap and blow up is not really a surprise. And it's not W3 that killed your PSU, it's the CPU and the GPU
You cannot expect games to not stress your hardware, they're supposed to.
Also, wish you good luck with the Corsair CX:
http://www.hardocp.com/article/2015/01/21/corsair_cx750_750w_power_supply_review
It got a "failed" rating and "no reason to buy one whatsoever".
Basically expected as it's just a cheap Chinese PSU rebranded&sold as Corsair, but nowhere near their usual QC standards.