4890 crossfire woes!

[thepigf@rmer]

Hi all, having spent the last 8 hours or so rebuilding my old PC......

Bye Bye:

[email protected]
Arctic Cooling Freezer 7 Pro
Gigabyte GA-P35-DS3R
4GB OCZ DDR2 6400
BFG 9800GX2
OCZ StealthXStream 600w

And hello:

Q9550 soon to be overclocked
Titan TTC-NK85TZ Fenrir CPU Cooler
Biostar T Power i45
2 x 2GB Corsair XMS2 PC2-8500C5 TwinX
2 x XFX ATI Radeon HD 4890 1GB
OCZ StealthXStream 1000w

So everything was going well(ish) untill i had finally got Vista 64 up and running. Then I noticed only 1 display adaptor in device manager.

Then I checked out Catalyst Control Centre, no Crossfire options?

Double checked with GPUz....

As you can see i've set the PCI-E lane(s) to 8 as per the manual and connected the extra 4 pin ATX connector to the mobo. Plus my PSU has 2 x 2 6 pin PCI-E dedicated cables, so everything sorted there.

Only thing that i can think of is that i'm only using 1 Crossfire Bridge connector. The reason for this is i could only manage to find 1. I've googled the required amount of bridge connectors required and haven't found a definite answer.

Was slightly annoyed at the lack of bridge connectors supplied with the cards and motherboard though. 3 items with crossfire capabilities and not one connector? I found one in my cupboard from a previous build.

But anyway, if anyone knows what could be up? fingers crossed it's something simple.

I have checked both cards in the master slot by the way and they're working fine and i've also tried 9.4 and 9.6 cats.

 

[Alexrose1uk]

Perhaps try resetting bios? It doesnt look like anything is being detected in the second slot at all unless its got an unknown device entry.

 

[Destination]

Try each of the cards in the main slot individiually
Check each is functioning.

 

[[timko]]

Try each of the cards in the main slot individiually
Check each is functioning.

See this...

I have checked both cards in the master slot by the way and they're working fine and i've also tried 9.4 and 9.6 cats.

Anyway, to crossfire just two cards you only need one bridge. The extra connecting edge per card is for when you do 3way crossfire and then you will need two bridges. Having two bridges plugged in for a basic 2way won't give any performance advantage nor will it prevent it from booting so I don't know what's going with your rig

 

[mmj_uk]

Does the card that isn't being detected work on its own in the 2nd slot if you remove the one from the master slot?

 

[Destination]

^^ mehhh thats what i meant

not main slot, try each individually in other slot

sometimes you've to not only set bios speed of the slot but also ensure its active, not sure with your mobo.

 

[thepigf@rmer]

Fixed, all Crossfire settings on this mobo are enabled via 9 jumpers on the Mobo, bit old fashioned tbh. Jumper number 9 (the smallest) wasn't in the correct position........building PC's at night isn't the best idea (for me anyway)

Just installing some games to see how it compares (fps wise) against my old setup.

 

[Overslop]

See this...




Anyway, to crossfire just two cards you only need one bridge. The extra connecting edge per card is for when you do 3way crossfire and then you will need two bridges. Having two bridges plugged in for a basic 2way won't give any performance advantage nor will it prevent it from booting so I don't know what's going with your rig

Actually, using two bridges does give a small performance boost.

 

[moppy89]

This thread is practically screaming for Crysis Benchmarks

 

[[timko]]

This thread is practically screaming for Crysis Benchmarks

Not when the Q9550 is only at stock 2.83Ghz it isn't

 

[thepigf@rmer]

Not when the Q9550 is only at stock 2.83Ghz it isn't

Not anymore

The Biostar bios isn't as easy to get on with as the old Gigabyte one, for an overclock n00b like myself, that is/

Will try and source another bridge before I post some benchies, though.

 

[[timko]]

Will try and source another bridge before I post some benchies, though.

Here's some interesting reading on two vs one crossfire on only 2 cards...

http://www.google.co.uk/search?q=two+crossfire+bridges

 

[AMG]

I herd via AMD fourms that some mobos/GPU brands needs more than 1 bridge anyway :S

mine works with 1

 

[thepigf@rmer]

Some benchies of Farcry 2:

Loop 1 - [email protected] & 9800 GX2

Loop 1 - [email protected] & 2 x 4890's

Loop 1 - [email protected] & 2 x 4890's

Loop 2 - [email protected] & 9800 GX2

Loop 2 - [email protected] & 2 x 4890's

Loop 2 - [email protected] & 2 x 4890's

Loop 3 - [email protected] & 9800 GX2

Loop 3 - [email protected] & 2 x 4890's

Loop 3 - [email protected] & 2 x 4890's

Average - [email protected] & 9800 GX2

Average- [email protected] & 2 x 4890's

Loop 3 - [email protected] & 2 x 4890's

May post some more benchmarks when i get hold of a second bridge, but judging by some of the comments it doesn't seem essential.