Is 850W P/S good enough for 3x 8800 Ultra ??

djthewizz

Distinguished
May 20, 2005
56
0
18,630
I have the Termaltake Toughpower 850W (W0131RU) http://www.thermaltakeusa.com/Product.aspx?C=1245&ID=1509#Tab1
I would like to know if i add a 3rd XFX 8800Ultra to my rig, do i have enough power ??

Rig Specs:

Intel Core2Quad Q9550 2.83Ghz Oc'd @ 3.8Ghz (1790x8.5@1.23v
Asus Striker II NSE Motherboard
4Gb DDR3 1333Mhz Kingston Ram
2x XFX 8800Ultra x16 SLI
Creative X-Fi Extreme Gamer
4x WD 160Gb SATAII Raid 0
1x WD 250Gb SATA 150 (Backup)
1x LG DVDRW SATA
TT Armor+ Full Size Case: 6x 12cm LED Fan, 1x 23cm Led Fan


I did the power supply test on somes websites that was post here on this forum but im still not sure about this.
I wanna order a 3rd 8800Ultra before its all sold out so please, can you give me an answer fast.
Thank You.



 

theAnimal

Distinguished
Jan 21, 2009
2,370
0
19,810
Possibly. You'll need to use Molex to PCIe adapters.

Why not sell your current cards and get 2 GTX285?

Edit: Actually even 2 GTX260 will be faster than 3 Ultra.
 

MRFS

Distinguished
Dec 13, 2008
1,333
0
19,360
http://www.thermaltakeusa.com/Product.aspx?C=1245&ID=1509#Tab1

That PSU has 4 +12V rails:

18A on +12V1
18A on +12V2
30A on +12V3
30A on +12V4

96 Amps total


To avoid any cabling errors, I think you'd be better off
with the Corsair 850W, because it has a single +12V rail
rated at 70 Amps:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139009&Tpk=Corsair%20850W
($110 after MIR: heck of a deal!)


Newegg's price for Tt's W0131RU, by comparision, is $230:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817153043
(that's a big premium to pay for modular cables and multiple rails)

confirming:
+3.3V@30A,+5V@30A,+12V1@18A,+12V2@18A,+12V3@30A, +12V4@30A,-12V@0.8A,+5VSB@3.0A


You can buy the Corsair 1000W model at Newegg for $220 after MIR:
it has modular cables:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139007&Tpk=Corsair%201000W
http://www.corsair.com/products/hx1000/default.aspx


MRFS
 

MRFS

Distinguished
Dec 13, 2008
1,333
0
19,360
Oops! Just noticed that you already have the Tt model.

Sorry for my oversight!

p.s. check the power requirements of each GPU
and cable accordingly. Your PSU should have amp
ratings for each rail printed on a specs plague,
also on the retail box it came in.


MRFS
 

MRFS

Distinguished
Dec 13, 2008
1,333
0
19,360
Well, then, this is very misleading in their product specs:

"Four independent & dedicated +12V rails(12V1,12V2,12V3,12V4)
provides superior performance for PC system(combined loading of 62A)"


If the 4 rails are "independent and dedicated",
we should be able to add the individual amp ratings.

If a system draws near capacity on V3 and V4,
those total ~60 amps, leaving only 2 more amps
for the other 2 "independent and dedicated" rails?

HUH?

That's how I read "independent & dedicated";
others may interpret those words differently.


MRFS