Hi all, I currently have a Corsair AX850 PSU in my rig, but was toying around with the idea or upgrading it to the AX860i, due to it being more efficient, coupled with lower ripple and noise output. Question I have is, Is my AX850 PSU overkill for the system I've built? Can I get away using an AX760 or less?
You could get away with a 650 watt unit with ease. It's not worth changing in all honesty. You'd save maybe 10 pence every 200 hours of it being on, assuming it is 5w more efficient when idling.
I'd stick with the PSU you have, any efficiency savings will be wiped out and some by the cost of the new PSU...
I own a AX860i PSU and it a great bit of kit I you was build a new pc I would say get it but if not I would stick with what you got for now
One of the reasons I purchase a very high quality PSU is because I overclock my CPU and sometimes my single GPU [MSI GTX 980 Ti Lightning LE]. As far as having enough watts, you have it already. I like very high quality power supplies because they supply quality [stable] power to my computer. I have no problem with the Seasonic Platinum series 660 watt in this regard. My computer build is nearly 4 years old, except for the video card and PSU. Electricity quality and problems where I live are a big problem and I usually swap out a PSU around 3.5 to 4 years on average, because of the beating they take. I expect this PSU to last at least 4 years, however.
I have a fairly similar setup to both of you and run it rock-solid, with both CPU and GPU at 100% load, 24/7. Running at approx 93% efficiency. I do this on a 460W PSU. Admittedly it's a very good one, but anything over 500W is overkill for a single GPU system.
In fact, my PC is currently folding flat out on both CPU and GPU, and my power monitor is currently reading me pulling 300W from the wall. That's a moderately overclocked 3770K and 980Ti. I could drop a Titan X in there and the PSU wouldn't bat an eyelid
So are we all saying to run an Core i7 3770K or above + GTX680 or above both running 100% load that a PSU rated at 460 watts is more than enough?
Like this one? http://seasonic.com/product/platinum-520/ Assuming a Fanless PSU is good enough for the occasional gamer.
Absolutely, I use the 460W version on my sig-rig and it's the best darn PSU ever. Well, the best 460W one anyway.
The efficiency difference isn't going to be that much. If you are concerned about efficiency, you want a lower wattage PSU for it to run optimally. Unless of course you are seriously considering a multi GPU setup at some point. I can't really say whether the voltage accuracy will make any difference with your Lightning. Your current PSU is very close to top notch already, and I'm sure the VRM's on the Lightning are also. I didn't see any improvement in overclocking my 780 when upgrading from a Be Quiet StraightPower E9 500W to my current 850HXi (I am considering multi GPU to power a 34" Ultrawide). It was limited by the chip itself.
It depends what the GPU is, and indeed what the other components are - when I was running 3DMark Firestrike with my 780Ti overclocked I was pulling over 600W at the wall, mostly from GPU load. I know the 780Ti is nowhere near as efficient as the newer cards but GPUs are power hungry components, especially the older ones, and it's also worth remembering that different software provides different levels of load. I'd always err on the side of caution and advise a little headroom, particularly on the all-important 12v rail, and most 500W PSUs won't provide that. The 520W Platinum looks great, but dat price...ouch.
Platinum psus as most reviews say if your buying today are maybe a nice bonus but the costs and savings from the next best rating are minimal at best.
By my reckoning you'd shave about 100W at full load if you upgraded to an overclocked 6700K/DDR4 platform but kept the Ti - but point taken. 500W might not be enough for an older or more extreme single card setup, but for a newer single card system it should be plenty. Also, the fanless Seasonics are expensive, but that is the price of heavenly silence when maxed out
