How large PSU for 7970 CrossFire?

Discussion in 'Power Supplies' started by RaistlinZ, Dec 31, 2011.

  1. RaistlinZ

    RaistlinZ Diamond Member

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    I currently have a Corsair HX750 PSU. I'm sure 7970 CrossFire would be pushing it with this, but how large of a PSU would I need?
     
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  3. RavenSEAL

    RavenSEAL Diamond Member

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    You should be fine but I guess if you REALLY wanna be safe, around 900w should be the mark.
     
  4. Satire

    Satire Junior Member

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    7970 requires less power than a 570, so CF 7970 on corsair HX 750w will work fine
     
  5. lehtv

    lehtv Elite Member

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    Will work fine on a 750W corsair. 200W per card + 200W for the rest of the system (OC'd i7) ~ 600W/750W ~ 80% at full system load which is fine. Corsairs are designed to handle that sort of load without issues.
     
  6. BoomerD

    BoomerD Lifer

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    http://www.guru3d.com/article/amd-radeon-hd-7970-review/8

     
  7. Elfear

    Elfear Diamond Member

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    As long as you're not overclocking the cards much you should be fine. I was getting random shut-downs with the parts in my sig (cards were overclocked) on a quality 800W PSU. That happened playing Starcraft II and sometimes running through the STALKER: COP benchmark. My Kill-O-Watt indicated 770W at the wallplate. A new 1000W PSU solved the issue.
     
  8. DooKey

    DooKey Golden Member

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    If you are going to OC and OV the cards and run them 100% folding or something like that and run your CPU 100% folding as well then I'd go at least 850w. If you are just gaming then your 750 will be just fine.