I run a i7-3770k @4.9GHz, an Asus Strix Gtx970 with 124% user OC, hdd, ssd, 2x optical, Nzxt Kraken 280mm aio on a Evga G2 550w and it doesn't even blink at 100% system loads, the fan never gets fast and heat output is nothing compared to what the gpu will put out under stress loads.
Here's the thing about psus, they need to match the application. The G2 I own is a quality gaming psu. It's internals are built to withstand the abusive demands a higher powered gpu can demand, instantly. There's many psus on the market that are decent, but not built for gaming purposes, so you end up with very good office/small business/general use psus that'll last for years normally, but subjected to gaming stresses can last months, if not days or less.
80+ isn't a standard. It's a voluntary certification. Simply meaning that if you see 80+ Gold or Bronze on a unit, it's at least decent for office use. The vendor gave the psu to 80+ for efficiency testing and it passed. If there's no 80+ rating, then very likely the vendor has absolutely no faith in its psu, or knows very well that its claims of wattage/voltage/amperage outputs are serious fabrications or out right lies. That said, to get 80+ Gold, the internal components and circuitry, even the platform itself is usually much better designed and built than a plain 80+ psu.
Does size matter? Hah. Yes it does. The psu is the heart of the pc. It needs only to be strong enough to power the pc, and thats it. If you have a pc with max loads of just 300w, then that's all you need is a 300w rated psu. Need. What happens then is the psu is constantly at max, temps are high and you'll have to listen to the fan constantly screaming. The difference roughly between 50% loads and 100% loads is @2%-5% efficiency, really no big deal. The difference to the psu itself is huge. At @50% you hit the sweet spot, not only in efficiency, but also in power distribution and thermals. 50% loads run well into the acceptable bell curve of everything related, you've got power to spare, overhead, and nothing gets excessively hot or runs underpowered.
For your system, a good quality 520-550w will easily cover anything and most normally is far cheaper than its larger 620-650 brethren. CXM 550W, Seasonic M12-II 520w, Evga G2/G3 550w, Antec HCG 520w, XFX TS/Pro 550w and a few others will be perfect for your needs, wants and potential changes. Can you run a gtx1060 on 450w? Absolutely yes you can, but not with my OC demands, I prefer a little more headroom at that wattage output. But for a middling 4.3 - 4.5GHz OC and gpu at stock settings, 450w is plenty good enough. Which puts 550w at the most you'd ever have any use for. 650w will work just fine, have no power delivery issues of any sort, you'll just be spending money on something that has no chance of ever being used. Kinda like buying a Ferrari just to go to the store 3 blocks away and you live right next door to the police station. Nice, shiny, wasted toy.
Facebook
Twitter
Instagram