3 gpu psu?

[RyanWebber]

I have 2 6950's and 1 5850. Would i be able to run all 3 on a 750 watt psu? Or am I limited to two cards?

[kiwiasian]

You can't crossfire cards from two different generations. Furthermore...they are two completely different architectures.

[RyanWebber]

Im not crossfiring them......Now please answer the question that i actually asked...

[qed]

If you do not downclock and downvlotage the cards most likely you can't. Also, using the PSU at his nominal limit might decrease his life span.

[kokojie]

6950 is 200 watt max each right? 5850 is 160 watt? so that's 560 watts, leaving 190 watts to the system, which I think is not going to be enough, unless you have some really low power cpu/mobo, no HD and single stick of ram.

[yyduinihao0]

with roughly 200W left for the system should be enough. But any additional card are out of the thought.
Hope this helps.

[tunatime]

when you say 750w psu what model is it? if its a cheep one nfw will it run as the cheep ones have very low A on the 12v rail and even if its a good one your going to be running at close to max load killing your psu Efficiency causing it to pull more power then say a 1kw psu whit high Efficiency. aslo you have over $600 just in gpu and your going to cheep out on your psu i work on pcs all day and when a psu blows some times they take the whole rig spend $150+ and get a nice 1kw uint

[RyanWebber]

Thanks for all the answers guys. My idiot friend was telling me I needed a 1200 watt. I figured 1k would be ideal. It is a cheapish 750 so ill stay away from 3 cards.

[fcmatt]

Thanks for all the answers guys. My idiot friend was telling me I needed a 1200 watt. I figured 1k would be ideal. It is a cheapish 750 so ill stay away from 3 cards.

in an earlier post of mine describing a rig i am building i found a rosewill 1000watt PSU with 6 - 6 pin connectors
for around 120 dollars. Not the best, not the worst.. plenty of room to run 3 cards.

[sang]

Ive seen so much discussion on these boards thats always centered about total wattage. Total wattage is not the important factor in determining if your PSU will handle these cards - what is more important is amperage available on the 12v rail(s).

I have a 400watt Enermax PSU that puts out more 12v amps then a lot of 650+watt PSU's i've seen on newegg. Read the PSU laebels and make sure you have the power you need in the VOLTAGE you need.