Power supply question:
I've got an i5 4670k, overclocked to 4.2ghz, 16gb of DDR3, with Windows 10 running on an SSD, and I just got my hands on a used GTX 980 Ti, to replace my GTX 1050 (not even a 1050 Ti). Don't mock me, this shit is amazing by my standards and I love it (even the 1050).
But to move from the 1050 to the 980 Ti, I have to upgrade from my reliable old 400 watt Corsair power supply to a minimum of 600 watts (I hit some power supply calculators, and 400 watt was the minimum for what I had, and 600 watt is the minimum for what I'm moving into). I looked at some cheap power supplies, but I decided to skip "cheap" and go for "midrange", and settled on a Cooler Master MasterWatt 750.
The Cooler Master worked great for exactly one week, and then it picked up a weird problem where it's cooling fan would shudder and shake my entire PC every time the fan spun up from zero RPM (which the fan did every 10 minutes or so), along with making an obnoxious sound you could hear from clear across the room. I immediately returned the power supply and got a full refund, so now I'm back to running on my Corsair 400 watt and my (non-Ti) GTX 1050 while I shop around for another new power supply.
From what I was able to figure out, the failed Cooler Master used fluid dynamic bearings, which use pressurized fluid instead of bearings, which is theoretically superior, unless it fails, which mine did in a week. Also, I saw someone suggesting that fluid dynamic bearings aren't ideal for low speeds, which makes them a poor choice for a fan that turns off at low power and only drifts a little air through every ten minutes. Also, I saw someone suggesting that it's better to get older tech (sleeve bearings) made well than newer tech (fluid bearings) made badly.
To that end, I'm looking at a Corsair RM650x. I've been happy with Corsair, and I saw someone suggesting Corsair and EVGA for quality. It costs more than the Cooler Master did, but I'd really like for it to not fail, and the RM650x uses sleeve bearings, which leans towards the suggestion of "older tech made well".
I guess my non-specific question is... does this plan make sense?
Bonus question: The Corsair RM750x costs $20 more (Canadian dollars) than the RM650x. Is there any sense in moving up to 750 watt? The Cooler Master's efficiency was rated 80+ Bronze and the Corsair is 80+ Gold, so I think the Corsair doesn't need as much extra headroom as the Cooler Master did (if it even needed that at all). I can't picture anything I could do to this computer to make it need more power than what it already needs, but maybe I'm missing something.
Edit: Looking at the Corsair TX650M, it looks almost as good as the RM650x, but is a bit cheaper.
Edit2: The TXM is semi-modular, while the RMX is full-modular. Why would I ever not want that fat cable to the mobo to be connected to the power supply? That's the one cable everyone always needs. I think I don't understand full-modular.