750W Psu For 3x 7850 1x 6970?

[noedelx]

Good evening people

i bought 3x 7850's  (http://www.asus.com/nl/Graphics_Cards/HD7850DC22GD5V2/)
and already got a 6970 Mining (http://www.asus.com/nl/Graphics_Cards/EAH6970_DCII2DI4S2GD5/)

i plan to use these cards on my  Old gaming pc ( now mining rig)

Amd phenom 4x 955
Motherboard(http://nl.msi.com/product/mb/890FXA-GD70.html)   can host 4 cards without raisers ( these cards will fit )
only thing im not 100% sure on is the PSU i got for this Rig atm its a 750W Psu (http://www.coolermaster.com/powersupply/gx-series/gx-750w/)
it has plenty of cables to support the Gpu's its just not sure if 750W will be enought

i have no idea how much Watt its using right now i coulth try using my Current Gaming pc Psu  and read how much it uses and just add 450W ( 3x 7850) to it and see if its to much
heres my other Psu btw
http://www.corsair.com/en/power-supply-units/ax-series-power-supply-units/ax860i-digital-atx-power-supply-860-watt-80-plus-platinum-certified-fully-modular-psu.html

what do u think?

[RENDERING]

Go buy a watt meter like this http://www.amazon.com/P3-International-P4400-Electricity-Monitor/dp/B00009MDBU/ref=sr_1_1?ie=UTF8&qid=1389731481&sr=8-1&keywords=watt+meter

Find out exactly how much each one runs. Then google how many watts each new video card uses. Then add another 150W + if you are planning on overclocking.

Good luck!

[noedelx]

Go buy a watt meter like this http://www.amazon.com/P3-International-P4400-Electricity-Monitor/dp/B00009MDBU/ref=sr_1_1?ie=UTF8&qid=1389731481&sr=8-1&keywords=watt+meter

Find out exactly how much each one runs. Then google how many watts each new video card uses. Then add another 150W + if you are planning on overclocking.

Good luck!

my dad told me he'l bring one tomorrow ( he has one at work)  gues il give that also a  shot
and tonight il give the other psu a shot ( using my gaming psu to see how much watt it uses)
the 860I can read how much Watt it pulls from wall how much it actualy uses of that + how much it sends to cards etc ( pretty awsome)

card wont be here till friday anyhow^^

[atp1916]

Each 7850 will pull 110-120w, and the 6970 will pull 175-200w + that x4 chip = Cutting it close.

[noedelx]

Each 7850 will pull 110-120w, and the 6970 will pull 175-200w + that x4 chip = Cutting it close.

yea ^^ but since all it does is mining dont think that Cpu will pull that much Power else i coulth even disable couple of Cores ( fresh instal aswel of windows + il remove services that i dont need )
maybe linux might help  

anyhow the CM PSU is  suposed to easly run 750W anything above that wont be 80% Bronze  anymore etc
but till 751W it shud run without a problem^^

[noedelx]

also got a thread running @ overclock.net
seems the 750W build quality is horeble and cant even run stable above 600W wich mean it can easly kill my PC/cards
so il run the 860WatT psu for the mining rig and see if i can use the 750W in my main rig ( runnin only 300-400W atm)

[BrewCrewFan]

Watts are good.... but your missing the amps. You can have a 1300 watt psu and still be bad and unstable because of the amps. Your cards will draw off the +12 line and if it does not have decent amps your gonna run unstable cards.

Add in compacitor age onto the PSU, it degrades over time and give less bang for the buck. Becomes unstable under load and more of a risk of failing.

With that said I run a basic system off a 750 Corsair PSU, but only have 3x 270x's on them... I know the 7850's draw less power, but I am not 100% on the power draw of the other card. IMO, if you were only running the 7850's on it, it might be okay, with that extra card I would for sure look for a new PSU to run the 4 cards, most likely looking into the 850 watt range and a decent named power supply.


BTW, those 7850s will draw 1.225 ish on the vddc, you can drop it a bit, I got mine OCed and was able to drop the vddc to ~1.150

[noedelx]

yea found out that this 750W psu is garbage so il just use this 860W one wich is one of the best 860W psu's