How many 4890's can i run?

[Joshbad]

So i just got a 850 Watt power supply, with dual 30 amp 12v Rails for 60 amps total.
My mobo supports quad crossfire or SLI, but i dont believe the 4890's do.

I got a q6600@3.0 GHZ
4 GB of ram
some hard drives and dvd drives, 5 total
a X-fi sound card a wireless card and some LED fans.

How many 4890's can my power supply handle, and whats the most you can crossfire?

 

[JAYDEEJOHN]

Tri is the most Ive seen with the 4890s.
If your psu isnt set up for it, dont do it, is the underwritten law at these specs. Lower specs, you can bend a lil, but with this, I wouldnt reccomend it

 

[Hindesite]

I wouldn't push more then two 4890s with that setup. You need 1000+ if you wanna tri or quad (if you can even quad-fire 4890).

You'll get some wicked performance out of a 4890 crossfire, though. You don't need more then 2 to max out any game out there. You might also want to look into the 4870 X2. I don't know if I'd try to crossfire two of them on your current PSU, but just one of them is pretty incredible.

 

[Joshbad]

Okay thanks for your help guys.

 

[cjl]

Which 850 is it?

With a good 850, tri CF would definitely be doable. The 4890 supports up to quad, but you'd need a case and mobo that supports having 4 dual slot cards to do it. Quad would probably necessitate a 1000W PSU though.

 

[JAYDEEJOHN]

I agree with jonny guru on this one. He says if your psu is set for 2 cards, thats what it should run, set for 1 etc, set for 3 on and on, especially at these higher demands

 

[xaira]

you can go quad, for tri that psu should cope, but ud be most comfortable with two

 

[JAYDEEJOHN]

Quad shows lil improvement over tri, and often it worse, these arent x2 cards, so its a very small market

 

[orangegator]

We need to know what brand psu. Most quality 750W psu's have 60A on the 12V+. Since yours is 850W with only 60A (or less possibly), it makes me think this is a crappy brand psu.