Question PSU for running dual EVGA GTX 780 in non-SLI

[RaptorJester]

I am building a gaming rig with the following parts.

Motherboard: Gigabyte 970a-D3P
Processor: AMD FX
Memory: 16 GB DDR3
Tower Case: Corsair Obsidian 900D
Graphics: 2x EVGA GTX 780 (in non-SLI mode)

What is a good PSU that will handle my rig, have 2x 6-pin & 2x 8-pin connectors for the graphics cards, and room to add fans later?

 

[13thmonkey]

If you can do anything, it would be to not run an FX processor.

With regards to PSU, we'll need to know which FX, as a 4300 would not require special treatment a 95XX would need special consideration for the PSU (and in your case a new mobo)

 

[sizzling]

Well a single 780 recommended 600w with 42A on the 12v rail. For sli I’d say a minimum of 850w good quality psu.

 

[13thmonkey]

I hope you are getting this for cheap as performance will not be great

 

[RaptorJester]

In response to 13thmonkey's first post. What AM3+ processor would you recommend?

What brand of PSU would have the connectors to run my graphics cards?

In response to 13thmonkey's latest post I got the tower, video cards, and motherboard for free. I won't be using it to play high-end games.

 

[13thmonkey]

So the whole of the FX series is basically rubbish, so if you'd have paid for it i'd feel sorry for you.
FX4xxx and FX6xxx are ok, underpowered but don't overheat too much.
FX8xxx tend to be tricky to manage the heat from perform better, and are a little power hungry, can be unstable on some boards.
FX9xxx, your 970 mobo won't run them, then need a very substantial PSU, are hot as anything, difficult to keep stable.
I'd go 6xxx or later 8xxx's (can't recall the names). Vishera cores in the attached. https://en.wikipedia.org/wiki/List_of_AMD_FX_microprocessors

The SLI 780's were the last of the power hungry GPUs (before 2000 series), at 250W, they've got 3GB of vram which is OK, not great, but will be useable.

So that's 500W from the GPU's, 200W from CPU, plus overhead, i'd say you'll be tight on an 850W PSU, you're nudging a KW.

So is it worth running SLI, actually perhaps not, support is waning, if you are not hardcore gaming then a single 780 will be fine, and that gets you into 600W PSU territory, which is far more normal and achievable without spending loads on a PSU that will be overkill for anything else.

 

[RaptorJester]

To be honest, I wasn't planning to run the graphics card SLI. I was going to use them independently, one for each monitor.

Do you think a 1000W PSU would suffice?

What about the FX-6200?

What if the PSU doesn't have enough power connectors for the graphics cards? Can y-connectors be added to get the power connectors I need?

 

[DSzymborski]

Could you tell us a bit about how you do plan to use this build? Because having two GPUs for two monitors doesn't really make a lot of sense in this context. If it's just extra screen space you need, you don't need a second 780 just to drive it. You'd really need to be an edge case for this to be a practical plan, some kind of very specific workstation need.

 

[13thmonkey]

^^ agree, 1 780 driving two screens is perfectly fine. And it gets you down to normal power supplies.