need help deciding 9800gtx SLI (X2)

[jmbrettler]

Time to upgrade from the onboard graphics card and since my mobo (750a) is SLI compatible I was hoping to take advantage of this....

Originally I was looking at the 5770 for cost and low heat reasons but recently ran into a chance to get two 9800gtx Black Edition's which completely decimates 5770 and for the same price....but im worried about my PSU and do not want to upgrade the psu to run the cards in SLI....

The 9800gtx needs 2X 6pin connectors for EACH card...
My PSU is ULTRA 650 watt and only has 2X 6 pin connectors....

What do y'all think? Will I have issues running these cards sli with my psu?

Included are 2 standard (peripheral --> 6 pin) connectors

Would I put one card on these, and the other card on the 2 -6 pin connections from the psu? Would it work if I gave each card one 6pin from the psu and one peripheral to 6 pin connection? I remember reading somewhere that not providing power from psu can hinder performance and in some cases card may not even function...

any idea's, suggestions??

- Jacob

P.s THANKS!!!

 

[Tom20]

Depends on the amps. Check either on the label on the PSU or go to Newegg and look at the picture of the label there if you can't be arsed to open the case.

 

[jmbrettler]

Input Voltage: 115 ~ 230

+3.3V: 24 A

+5V: 32 A

+12V 1: 38 A

-12V: 0.6 A

+5VSB: 2 A



I'm clueless when it comes to electricity =D

Apparently the OC edition needs 26amps for 12vrail....

so to run 2 cards , i need a PSU with 52amp for 12v rail ?

 

[Tom20]

Yeah don't think that PSU will do it mate. I'd look at Corsairs PSU's.

http://www.overclockers.co.uk/showproduct.php?prodid=CA-018-CS

 

[jmbrettler]

thats a huge bummer, since I can't really afford the 2 cards and a new PSU...
was hoping to get away from my stock CPU cooler hehe

hmmm....

anyone out there running similar SLI setup with 650 watts on 38amp 12v??

wow that 750watt looks niceee

 

[Tom20]

Or you could just run the one GTX until you can afford a new PSU?

 

[jmbrettler]

was thinking about that too but my gf just hates when I spend extra now, only to spend more later ... I'm sure X-Mas sale on PSU I can find something

 

[Tom20]

There's bound to be mate. I'd recommend Corsair since they've won many awards or PC Power & Cooling PSU's are good too.

 

[jmbrettler]

Ty for your opinion and suggestion!

 

[Tom20]

It's ok! Always here to help.

 

[ToTTenTranz]

TBH, I think you would have no problem at all using two 9800GTX with that PSU.
Even if it doesn't have enough PCI-E connectors, you can use one PCI-E conector for each graphics card and one 5V to PCI-E adapter for each. I do that with my PSU when connecting to my HD4890s and have no problems whatsoever.


However, those 9800GTX are 512MB or 1GB?
If they have only 512MB each, I think you'd be better off with the single HD5770 1GB, in the long run.

 

[brandonwh64]

I have a LSP 650 (in my HTPC) that at one time i ran two 8800GTS 640mb sli with a E5200 @ 3.2ghz on a XFX 680I LT SLI mobo and i had 0 problems but i dont know if the 9800GTXes need more amps

heres a old pic

 

[jmbrettler]

brandon you have me thinking it just may work !! Thanks!

http://www.tomshardware.com/reviews/geforce-radeon-power,2122-6.html

according to this site, would I not be okay with my current PSU ??

 

[jmbrettler]

also, after more review, it seems that getting my mobo to work in SLI is a pain in the @ss, often ending in failure... thinking about the 5770 again....

one pcie slot is 16x and the other 8x, and in sli they are both 8x, so technically not really worth it??? too much information, im too newb to figure all this out LOL

=D

 

[brandonwh64]

my 680i rocked at SLI! i would recommend

XFX 680I LT SLI Motherboard
XFX 780I Motherboard
XFX 790 Motherboard

Those are good for SLI

 

[MKmods]

which completely decimates 5770 and for the same price....but im worried about my PSU and do not want to upgrade the psu to run the cards in SLI....

this is a toughie.. First they dont "decimate" the 5770 (especially if using a 1920 X 1200 screen) maybe better but not decimate.

Second there is the memory 512 or 1gig?(1 gig is better for large screens), than there is the mobo, is yours the old PCI 1.0 or the newer 2.0 version (1.0 is X8 on each slot, 2.0 has X8 but its the equivalent to X16 on the old 1.0)

Power supply should be plenty for 1 or 2 cards (just use 1 adapter for each card)

 

[jmbrettler]

I will be using 1920X1080..
the memory on the 9800gtx is 512.

not sure about old or new version PCI 1 or 2.0.....how can i figure that out?

 

[MKmods]

whats the model of the mobo?

if its this one its 2.0
http://www.newegg.com/Product/Product.aspx?Item=N82E16813141010&Tpk=xfx

EDIT: for me being senile

LOL sorry my mistake, I think the 750 chipset stuff is all 2.0 (the 650 and earlier was the 1.0 stuff)

With the 24, the 1gig video cards will come in handy (I use 2 of the 5770s) But its hard to say how 1 will be compared to 2 of the 9800s (thats the hard part).

Personally 2 of the 9800s would look cool (but may struggle a bit by the lack of memory with really high settings) But if you wanna crank AA than the newer ATI cards rule

(see its a hard choice)

By the way what games do you play?

 

[jmbrettler]

decisions decision decisions. Thanks very much for all the input!
Right now Im playing COH,COD4,Left4Dead, HalfLife, N4S UG, GTA but am looking to expand, in terms of new genre and better graphics gaming experience...

I also want a gpu that will be overkill for 1920x1080 on high settings, which is something I have never experienced yet, as I am still operating with on board video lol..

 

[MKmods]

take a look at the 5850 (its $300 but really nice and DX11 for the future)

On the games you have the 9800s would be fine but for future ones you will need an upgrade and the Nvidia ones arent out yet. (I couldnt wait so I got the 5770s)

Personally I have had better luck with Nvidia but these new ATI cards and drivers are much better than before.