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I am building a new computer and would like to double check on the power supply. I am using Building a PC, Part VI: Rebuilding as a guideline, updating parts to newer ones available, but am staying within the lines so to speak (aside from the GPUs).

Overall this will be a gaming rig with 2 x 6870s in crossfire, 4x2 DDR3 DIMMS, i7, etc. (I am still looking into water cooling units and don't know how that will impact psu requirements.)

I have churned the expected setup though the psu calcs on newegg, outervision, and used ibuypower as a reference point. These break down as:

  • outervision - 501W
  • newegg - 780W
  • ibuypower - 850W

I understand these are approximations/best guesses. Based on the Jeff's article above and the reviews on newegg I believe I am going to go with the CORSAIR HX Series (approximate current prices):

  • 650W - $120
  • 750W - $140
  • 850W - $170
  • 1000W - $230

It's probably silly to even be concerned about going up to the 850W at this point based on what I want to do with the box. Should I even be looking at the 1000W or is that just totally unnecessary? (not that that's a bad thing)

I am really enjoying this process and appreciate input, thanks.

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With with 2 x 6870s in crossfire, 4x2 DDR3 DIMMS, i7 it's not silly to seriously look at the 850W powerplant. – Sathya Dec 7 '10 at 5:04
Also wanted to mention I am not looking at any OC at this time. – blu Dec 7 '10 at 5:06
@Sathya Agreed, it's really down to the 850 vs 1000. – blu Dec 7 '10 at 5:09
If you can stretch it, it's worth getting the 1000W. A good PSU lays a solid foundation & it's not like the 1000W will consume 1000W - the actual power consumption will be as required. – Sathya Dec 7 '10 at 5:16
With Sathya on this - if you can afford it, kick in for the 1000W. – user3463 Dec 7 '10 at 6:42
up vote 3 down vote accepted

As mentioned in comments,

With 2 x 6870s in crossfire, 4x2 DDR3 DIMMS, i7 and a possible water cooling you should be looking at a 850W PSU. And if you can stretch it - a 1000W would be ideal. A good PSU can help your system and can cope up with any possible future upgrades.

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