780 GHz times two on a 750w?

SAFry

SAFry

SAFry

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I guess this board gets a bit repetitive after a while?

I got two 780 GHZ and an AMD hex core, and a bunch of hard drives, ran it through a calculator which didn't have the GHz OC version of my cards as an option, BUT it said 718w.

However, elsewhere I've read that a full loaded GHz edition card pulls 300w more than an idle on. So 300*2= 600 before anything else! I've tried the cards out a bit hot and nothing bad happened. It's a 750w Superflower Gold Leadtex, don't really want to push it too hard just in case.

I was considering getting an AMD Piledriver FX-8 Eight Core 9590 Black Edition 4.70GHz and upgrading the PSU to a SuperFlower Leadex Platinum 1200W Fully Modular "80 Plus Platinum" Power Supply just to be sure..

Or maybe I should get one of those £20 wattage meters that goes on the socket just to sanity check if I'm actually pulling anything near what the calculators say I am?
 
I wouldn't do it and my cpu is not as power hungry as yours. I am seeing 422w at the wall when gaming with a single 780. I guess I would be somewhere around 680-700w with a pair. I would want more than 50-70w headroom. Ideally I would want a minimum of 850w.

Don't waste your money on the 9590. It's a ridiculously priced (for AMD) cpu that should never have been released. What do you have at the moment? A 8320 should overclock to 4.5Ghz easily enough on a decent board.
 
CPU is a 6300 OCed to 4.2GHz, yeah my mate was winding me up saying that I'd probably get CPU bottleneck but so far I've seen no indication of that happening. Maybe I can just hold out on for the CPU/Motherboard upgrade until I can jump to DDR4.

So should I upgrade to the 1200w? It's only a £15 more than the 1000w and I figure I wouldn't have to buy another PSU for at least 5 years. I've not heard the fan on my 750w kick in yet but then I'm still running 1080 and I'm doing all this to go to 4k so it might start running hot then.

**edit** actually it's more like £25, I'm sure a 1000w will be fine. Even IF I upgraded the CPU which I think I wont now.
 
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850w would be enough without the 9590 (please don't waste your money on that) but if you wanted 1000w it's not that much of a price jump and would see you able to run any pair of cards (apart from dual gpu cards) in the future. The thing is Nvidia cards are getting extremely efficient while AMD cards seem to be going the opposite way. A pair of GTX 970's in sli have a total system power draw of around 450w!! I can make my pc with a single 780 pull that much. :eek:

Take a look at the EVGA Supernova G2 psu's. They are built by Superflower and are based on their own Leadex Gold platform but come with a whopping 10 year warranty. The 1000w G2 is £15 cheaper than the Superflower and they are basically the same psu.
 
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Based on my setup (I have power monitoring setup but only 1 GHZ edition - my peak so far is 419 watt) I would guess at a peak of ~650watt* under load in a game like say BF4 not far off pastymunchers estimate - personally I stuck an 850 watt in so as to be comfortable should I go SLI with this setup.



* Unless you have a really mental OC going on or a CPU that is significantly more power thirsty than a 4.4GHz 4820K.
 
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pastymuncher said:
I wouldn't do it and my cpu is not as power hungry as yours. I am seeing 422w at the wall when gaming with a single 780. I guess I would be somewhere around 680-700w with a pair. I would want more than 50-70w headroom. Ideally I would want a minimum of 850w.

Don't waste your money on the 9590. It's a ridiculously priced (for AMD) cpu that should never have been released. What do you have at the moment? A 8320 should overclock to 4.5Ghz easily enough on a decent board.
Click to expand...

Remember to take the PSUs efficiency into account.
422 w from the wall with a gold rated PSU is only around 375 W from the actual PSU.
 
pastymuncher said:
Take a look at the EVGA Supernova G2 psu's. They are built by Superflower and are based on their own Leadex Gold platform but come with a whopping 10 year warranty. The 1000w G2 is £15 cheaper than the Superflower and they are basically the same psu.
Click to expand...

Funny, I had an EVGA 750w and it broke after 11 months, RMAed it and they left it until the very last day and Overclockers sent me the Superflower in the end.

I got a free smart meter for the house and managed to do some testing. At idle the whole house draws 500w. When I put FurMark test on at 4k with no AA, I managed to get 70fps (woo!) and got both GPUs upto 100%

Total power consumption jumped up to 1200w! Wow, so that's 700w right there, well done Superflower PSU, what a trooper, well for 60 seconds anyway.

Just glad my 1000w Platinum is arriving tomorrow. :D Should do me even if I need to upgrade the CPU at some point.
 
Iirc, with a pair of non ghz wf 780's, my power draw at the wall in games is around 650w, (will check for definite). Most I've seen drawn was 740w under 3d mark fs combined test. First used a corsair hx850 before moving to a 1000w superflower psu.
 
SAFry said:
Funny, I had an EVGA 750w and it broke after 11 months, RMAed it and they left it until the very last day and Overclockers sent me the Superflower in the end.

I got a free smart meter for the house and managed to do some testing. At idle the whole house draws 500w. When I put FurMark test on at 4k with no AA, I managed to get 70fps (woo!) and got both GPUs upto 100%

Total power consumption jumped up to 1200w! Wow, so that's 700w right there, well done Superflower PSU, what a trooper, well for 60 seconds anyway.

Just glad my 1000w Platinum is arriving tomorrow. :D Should do me even if I need to upgrade the CPU at some point.
Click to expand...

At the wall!

You still had some headroom left, because your PSU pulling 700w from the wall was only supplying the PC with 630w, you had 120w of head room, which is about 20%!

Tacitus said:
I think people really overstate how big a PSU they need...
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They really do.
 
Oh sorry for overstating my PSU requirements, I was worried I might over tax my PSU and damage it or my system. Also 700w AT THE WALL was the increase when I started the benchmark, not the total consumption. And my CPU wasn't fully taxed at the time either.

I could always return the 1000w, I haven't opened it yet. Also didnt want my PSU having to work too hard and get all hot and noisy. And I was thinking of future CPU upgrades.

The Gigabyte website says the GHz want 600w each which is obviously overstating it a bit.

End of the day I've got better things to spend money on if you think the upgrade is really pointless?

**edit**

p.s. apologies if I sounded a bit arsey above, maybe you caught me at a low ebb of buyers remorse. I still haven't opened the 1000w PSU, will leave it 24 hours. Every calculator I did had me pretty much on the borderline for a 750w PSU, experimentation tended to back that up although I haven't actually tested it all the way to a brown-out. I just think I would worry less knowing that I had enough power for my GPUs and an overclocked CPU upgrade or whatever the future holds. As long as it's not another overclocked 780 GHz! I mean 850w would probably be fine but I'd hate to have to buy yet another PSU. AND I can always recoup my costs on the 750w by sneaking it into another build ;)

Receiving my 28" 4k Asus monitor today and seeing it in action has definitely cheered me up, nothing I've tried in 4k has actually pushed the GPUs anywhere near what the benchmark did.
 
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Oh, it's okay. PSU calculators, in my experience are never that good, it seems their intention is to get you to purchase a new PSU, or puts in data that isn't accurate.

If I were you I would just try the current PSU you have in a usage scenario, play some demanding games, monitor power draw at the wall and see how it goes. You're not going to kill anything, this is why people suggest getting a PSU by a known reputable manufacturer, so that you can actually make use of its rated capacity.

The good manufacturers build their PSUs to support a higher power output than is specified to ensure it can at least reach its rated output. As it's pointless having a say, 750W PSU if it can't deliver 750W without falling over.
 
Done a quick blast just now on bf4 with my setup. The highest my wall meter showed was 620w at the wall. Spec below.

17 4790k @4.7ghz on 1.300v
asus m6 formula Z87 mobo
8gb 2400mhz ram
x2 gtx 780 wf cards at stock
1x 250gb ssd
1x 1TB hdd
11 case fans
1000w superflower platinum psu

Mostly seen power draw being displayed as 550w ono for the duration of the time i played, should add that this figure includes my monitor too, as the monitoring unit i use is a 5 plug strip model.
 
I've just written to OC to ask if I can return it unopened. I've still never even heard my 750w PSU fan kick in. Tried to make it brown out using Prime and FurMark but it all runs fine. I'm sure if I do actually have a greater power requirement in future OCs will be glad to ship me one.

By the way, in case you were wondering, 4k gaming is a bit so-so, actually not as good as 2560x1440 with the AA turned up for most games! But that's a discussion for another board...

Cheers guys.
 
There are 2 reasons that PSUs tend to be over stated/recommended a fair bit over requirements:

1) Recommend someone needs say a 600 watt PSU where it would be quite comfortable with a good brand and you can almost guarantee they'll go buy some noname 550 watt that explodes trying to put out 70% of that then come back and claim you gave them bad advice.

2) You want the PSU running with a fair amount of headroom so that its running cool, quiet and stable giving the best long term results especially as the capacitors (and other components) will slowly degrade over time so depending on how long people keep a system running its usually a good idea to leave a bit of margin for that.


EDIT: Oh and I mostly agree on 4K gaming also - generally I'm much happier at 2560x1440 - there are some exceptions and it doesn't help that most of the current 4K panels aren't the most responsive for faster paced gaming.
 
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