Crossfire on a non crossfire board

[Guest]

hello everyone,

I have been thinking for the last few days, is it possible to xfire on a motherboard that has ONE PCI-E x1 slot and ONE PCI-E x16 slot,
I remember a guy powering up a 9600 GT from a pcie x1 to x16 slot converter to use it as PhysX processor, so I think the PCI E x1 can provide the 75 watts of power...

Another thing that got me thinking was that Asrock made a nforce board that could crossfire, so that means crossfire is in software not in hardware? and that you can SLI in AMD chipsets (software?)....

I just ordered a 4850 and I am thinking of getting a cheap 4830 to try to crossfire (if someone would lend me their 4830/4850 that would be awesome ;P ).

So my basic Idea is:

MOBO-->PCI-E x1--->PCIE x1 to X16 adapter (stretchable)--->4830-----|
-------------------------------------------------------------------xfire connecter
MOBO-->PCI-E x16----------------------------------------->4850-----|

Hopefully that above diagram helped (XD)

from that evidence I think I may be able to crossfire although bottlenecking it but worth a try...

can someone with 2 radeon cards lying around give it a try?

the PCIE x1 to x16 converter can be found here

Evidences:

SLI on AMD board
8800 GT with 9600 GT (pci E x1) physX
crossfire on SLI board

Opinions HIGHLY appreciated,

Thanks!

 

[henydiah]

a good idea, I'm happy with the idea odd strange, so
if successful do not forget to share the results of the
score, good luck

 

[simon12]

Interesting, it could work but running a card in a 1x slot will limit its bandwidth so I think there would be no performance gain if you did get it to work.

 

[Guest]

Interesting, it could work but running a card in a 1x slot will limit its bandwidth so I think there would be no performance gain if you did get it to work.

I'll gain performance, just only 1/16th of it but still gaining performance...

And it'll be weeks before I get money to buy a 4830 and the adapter...
I just wanted to give you guys my hypothesis

 

[simon12]

I like your idea but the 4830 will bring the 4850 down to its speeds so the 1/16 performance gain will be wiped out and more. Also I think the 1/16 performance gain is wrong anyway I read an old article which showed on most games running 2 cards in a 16X & 4X slot gave worst performance than a single card see http://www.tomshardware.com/reviews/crossfire-pci-express,2095.html .

 

[Guest]

I like your idea but the 4830 will bring the 4850 down to its speeds so the 1/16 performance gain will be wiped out and more. Also I think the 1/16 performance gain is wrong anyway I read an old article which showed on most games running 2 cards in a 16X & 4X slot gave worst performance than a single card see http://www.tomshardware.com/reviews/crossfire-pci-express,2095.html .

Well, I think that you're referring to the 965 chipset, I can only think of one possible thing, the other 4 PCI E lanes are not connected to the NB directly instead, connected to the SB then to the NB. Anyways, I guess I'll just have to test it myself to prove it to myself ;P. Another thing I can come up with is that 965 is WAY TOO OLD and AMD uses abit different architecture...

 

[simon12]

Good luck let us know how you get on.

 

[bojo600]

tht looks like a really good idea actually, i have 2 hd5750s and a pcix1 slot, i might give it a try but that would have to be a couple weeks from now cuz im trying to find a job, maybe when my comp needs an upgrade ill buy that n a lil 50 dolla grafix card for some 3 way sli. if you sent me one in the mail i could test it but im just a random person on the internet so whatever.

 

[jb6684]

In Crossfire the system will run at the speed of the Slowest card. So, RAM & GPU speeds will drop to 4830 levels...

Second that adapter is a neat way to plug in a second PCI-E x16 card, but, it can't perform miracles it will only make it Physically possible to install the card, but, will still have only ONE PCI lane available to the second card.

I tried the Crossfire of a pair of 5770's on a motherboard with a Blue x16 PCI-E and Black x4 PCI-E slot. Performance gains were tiny:

Results DiRT 2 @ 1600x1200 (max'd out with AA x4)

Single 5770 : 50.1 FPS
Dual 5770 : 51.9 FPS (yeah, hardly worth $100 for 2 FPS NOTE: x16 / x4 slot ASUS motherboard)
Dual 5770 : 79 FPS (x8 / x8 ASUS motherboard (identical system except I changed to PRO version of the MB which supports x8/x8)


You will get better results is you return the 4850 and get a Single faster card.