today a lession has been learned.....

[mac124]

The thing about higher end psu's IF the fail you stand more chance of your rig surviving due to the extra protection, afterall nothing is guarenteed to never fail.

Fingers crossed you haven't learned an expensive lesson here.

 

[Count123]

now am worried cuz am using diablotek 600 watt that cost $40 after ma 500 watt [font=Tahoma, Arial, sans-serif]ModXStream Pro died on me.[/font]

 

[Edgeyforsure]

okay got my new psu, no post, no beep, thinking mobo has gone, tried cmos reset :/

 

[Luger718]

when it comes to psu's i like corsair antec and seasonic.... top 3

 

[PurpleTrance]

Antec TruepowerNew FTW Comes with about 50 certifications lol. And it's semi-modular too. Very solid build and great all-round quality. Can run upto 8pin+6pin GPU off a single rail.

 

[Edgeyforsure]

well i did a cracking job with the PSU considering its none modular, shame i just had to undo my 40 mins of work. mobo has just been sent off, and may i just say, the corsair seems to weigh at least 4x as much as my old PSU. looks ALOT nicer even came with accessories haha, (4 black screws, case bade, inside some nice velvet bag) i dont care so much about them, but it is still very nice.

fingers crossed the mobo replacement will sort it....

 

[pursuinginsanity]

Remember to add a suitable extra margin if you're planning on overclocking cpu/graphics fiercely. I forgot and will have to take it easy.

And who has told you that? The HX 850 is one of the very best PSUs on the market, and I assure you, you won't bring it to it's knees no matter how much you overclock your signature machine. That PSU is enough to OC a 950 + 2 480s. Sandy uses less power than Nehalem, plus P67 doesn't have a power hungry northbridge, AND the 570 uses less power than the 480. You would even be fine to overclock if you were on the HX 750.

You don't need a kilowatt PSU for your machine, far from it. The whole system will draw in the neighbourhood of 600 watts from the wall, and then efficiency must be taken into account, and will drop that 600 down to 540 or even less. You've got miles of headroom.

 

[sotonswan]

And who has told you that? The HX 850 is one of the very best PSUs on the market, and I assure you, you won't bring it to it's knees no matter how much you overclock your signature machine. That PSU is enough to OC a 950 + 2 480s. Sandy uses less power than Nehalem, plus P67 doesn't have a power hungry northbridge, AND the 570 uses less power than the 480. You would even be fine to overclock if you were on the HX 750.

You don't need a kilowatt PSU for your machine, far from it. The whole system will draw in the neighbourhood of 600 watts from the wall, and then efficiency must be taken into account, and will drop that 600 down to 540 or even less. You've got miles of headroom.

Hi,

My thinking that I shouldn't push it was based on a safety factor which I hadn't stated, and some real world data (which I'd misinterpreted).

Safety factor - some people would call this completely arbitrary, but given that PSUs will degrade over time and get noisier at peak load, etc etc I didn't really want to exceed 75% of the stated maximum - so thats 75% * 850 = 637.6. That's inside the case, not at the wall. So I had this general figure of 650W in my mind when I read this review of a UD7 and 2xgtx 570.

Theres a nice table in the Power Consumption section which gives measured wattages for 5.1 Ghz overclock and stock. Now unhelpfully he's mixed at-the-wall system wattages with in-case mobo/ram/cpu power. I'd interpreted the 668 W stock power draw as being in-case. It isn't. I's at the wall. So in case is 85% * 668 = 567W at stock or 85% * 765 = 650W at 5.1 GHz.

So I'd originally (incorrectly) interpreted stock clock power (668) as slightly over my (if you like arbitrary) safety limit. But it seems that I can do close to a 5Ghz overclock and be at my safety limit.

So after all, I agree with you. There's plenty of room here. And we have someone's real world measurements to prove it. If only I'd read them properly. :/

Forgetting this particular PSU and graphics cards for a moment, we still see that the difference in power draw (at the wall) from stock to 5.1Ghz is 765 - 668 = 97W, which is 85% * 97 = 82W in the case. So the point still stands that an agressive overclock can require quite a bit of extra juice, which is worth allowing for in your PSU rating choice.

ATB

 

[Stryker64]

The safety margin tends to be never go over 80% load, because a lot of cheaper PSUs may GG EXPLODE once you go over that, so it's always a good idea get a nice safety margin. Of course with something like the HX-850 with it's quality parts you'll probably be able to get it to 110% without it exploding. But it's just a nice safety margin to have, since if you don't push a subpar PSU to the limit, it's less likely to explode.