Crossfire wattage question?

Hi guys,

I want to upgrade my PSU in the near future and I have a question about how much overhead I might need, and I'm hoping I can get some feedback from somebody who has a similar setup or experience with such a setup.

I currently have a 650W PSU with the AMD FX8320 and an R9 380 G1 gaming.

I am going to upgrade my PSU regardless, but I was entertaining the idea of possibly grabbing another 380 and running them in crossfire down the track. I already have one 380 and I love it so I won't be upgrading to a 390/X. If I change my GPU set up it will be with a secondary 380 (inb4 people tell me to get a 390/970).

So my question is what size PSU should I get in order to account for this potential upgrade, remembering that my CPU is a fairly power hungry unit. Could I get away with a good quality 750W or will I need an 850W to run this set up?

The only gripe I have with the 850W is that if I don't actually get another card it will be massive overkill for my single GPU setup.

Any feedback is appreciated! :)

honestly. you can get away with the 650w. I used to run two R9-270x cards in crossfire with a 4760k overclocked to 4.5ghz on a 650w PSU. though if you wish to feel a bit more comfortable consider a 750w at the least.

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Ok great, so really a 750W is all I'll ever need and the 850W is just over the top.

It's good to know I could probably use the 650W as the new PSU won't be a dire upgrade. I will probably still upgrade as I want a more efficient unit and I wouldn't mind a zero RPM style fan.

Thanks for the reply.

I'd do a 750w for lets say two 380x cards (or 380s) for headroom. and anything else for example maybe two R9-390x cards or power hungry cards. then consider the 850w.

750w is ok I ran 2x 7950s with one no problem, [email protected] as well.

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Ok cool. Thanks guys. I had noticed whilst doing some research that there was a significant jump in power usage between the 380 and the 390.

Like I said I won't be using a 390 so I might start looking for a 750W unit then :)

this is my experience with multi GPU set ups.


seriously don't its not worth the headache unless you're playing at 4k.

most games don't support it, those who do, do it poorly and only a small handful fully support it, but it will never be smooth because of micro stutters which are there no mater what.

  • If you decide to go with a single R9-390 then a 650W unit should be more then fine, if its a decent one.
  • If you decide to go with the dual 380 route, a 650W if a decent one might be okay
    But a 750W would not hurt.
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i ran a 650w with a 6350 oced to 4.7 and 2 r9 285's (the 380 predecessor) worked great.

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