1500W PSU is No longer required?

[MrTeal]

16 awg is thick enough for 2x6 pin as well as 1x8 and 1x6 together. I would presume that any decent psu manufacturer would use even thicker wires when using 2x 8pins on the same wire or we'd be hearing a lot more about wires melting.

16awg can handle 22A which at 12v comes to 264W. When you consider that up to 75W (it varies greatly for different card models) comes via the PCIe slot itself, and that most top end cards don't draw more than 250-300W, 16awg is borderline OK in those situations.

It's when you have overclocked dual gpu cards that you really need to double check, or use 8 pins from separate cables.

On the other hand, The new 1080's with 2x 8 pins will never get close to making those wires too hot.

I think you're getting confused by the difference between a conductor and a cable. A power supply that uses 18 gauge and one that uses 16 gauge are both fine in all the scenarios you describe, though the 16 will suffer a little lower self heating and voltage drop. Each conductor is either 0.823 mm² (18ga.) or 1.31 mm² (16 ga.), so even with 2x8-pin connectors and 18 ga. you have six 12V conductors and essentially the same cross-sectional area (and much greater ampacity due to greater surface area) as a 10 ga. conductor.

Edit: Really the big limit on large chain PSU cables is the modular end. Most cables that have dual plugs on the GPU side still run each conductor through a single contact on the PSU side, so if you have two connectors running off six wires (three 12V and three 0V) they're all running through six pins on the PSU side and you're limited to ~30A per cable by the ~10A per pin spec for the Minifit Jr. depending on what terminals they used.

 

[Deders]

Ahh, hadn't thought to factor in that there were multiple wires. Makes more sense now.

From what I remember the ATX spec gushes are still accurate?

 

[Smoblikat]

you must have not been around a lot in the past ... 7 years.

a 1200w PSU will quad-SLI with headroom to spare.

This ^^

I used to run a Z77 extreme11, overclocked 3770K, 10+ HDD's, DVD drives, lots and lots of LED fans/cold cathodes, plus 4Xhd6970 in quadfire. Theres no way youre going to tell me I didnt need a 1300W PSU.

 

[philipma1957]

Hello;

Considering how power efficient graphic cards are these days is there any need to go higher than 1200W. Seeing how more than 2 way sli is no longer officially supported. With two new titan which will be released, is there a reason to go 1500W?


Thanks

this is real simple get an evga 850 watt titanium psu . ten year warranty

jguru rates it well it is around 220 usd

 

[Red Squirrel]

For me it's not so much the '1500W' that concerns me, it's the performance of the power supply itself. And funnily enough it seems that the AX1500i is one of the best power supplies ever made, and I think there's an EVGA 1200 watt one also widely considered to be excellent. I don't see many 750W power supplies winning performance awards on jonnyguru (which I use as a bible for power supply reviews), but I might be mistaken.

I think there are rigs where larger power supplies are warranted but 1500W is indeed very generous.

Yeah quality is better than quantity, a lot of cheaper power supplies can't even handle running at their rated capacity. There are reviews out there where they load test power supplies and they die before they even get to the rated load.

 

[dave_the_nerd]

This ^^

I used to run a Z77 extreme11, overclocked 3770K, 10+ HDD's, DVD drives, lots and lots of LED fans/cold cathodes, plus 4Xhd6970 in quadfire. Theres no way youre going to tell me I didnt need a 1300W PSU.

I might tell you that - what was your power draw at the wall, and how efficient was your PSU?

 

[mnewsham]

This ^^

I used to run a Z77 extreme11, overclocked 3770K, 10+ HDD's, DVD drives, lots and lots of LED fans/cold cathodes, plus 4Xhd6970 in quadfire. Theres no way youre going to tell me I didnt need a 1300W PSU.

well assuming you aren't doing a stupid OC on the HD 6970s you'd be using at MOST ~1150w, maybe 1200w.

And that's the worst case scenario which I cant think of a single game that would manage to utilize that much power.

a 1300w PSU makes sense for that build, but more to the point, that build doesn't make much sense unless it was for Bitcoin mining during that craze.

 

[Smoblikat]

I might tell you that - what was your power draw at the wall, and how efficient was your PSU?

No idea what my wall power draw was, but it was a good Platinum rated PSU.
http://www.newegg.com/Product/Product.aspx?Item=9SIA8EF3281120

well assuming you aren't doing a stupid OC on the HD 6970s you'd be using at MOST ~1150w, maybe 1200w.

And that's the worst case scenario which I cant think of a single game that would manage to utilize that much power.

a 1300w PSU makes sense for that build, but more to the point, that build doesn't make much sense unless it was for Bitcoin mining during that craze.

Originally was a bitcoin mining rig, had 3 6970's and an HD5970 in there at one point. But eventually it turned into just a ridiculous gaming rig with plenty of benchmarks/stress tests on the side. I also did a bit of folding on it.