Crossfire not working with Dx10

[blu9987]

Hello,
Right now I have 2 HD3870s running crossfire on vista ultimate 64bit edition. Games work fine using crossfire in dx9, but in dx10 only 1 card gets load. I verified this using 2 instances of GPU-z as well as having the Crossfire logo on the top right of screen. I've tried both Ati drivers and DNA custom drivers (which run better 😀) with no luck. Any insight on the problem?
Oh and im on service pack 2 with all updates. I tried installing some game fixes that i found via google but "the update does not apply to this system" came up so i'm assuming they're already installed.

Thanks a ton for the help.
i've been reading around tomshardware for awhile finally made an account for this post.


screenshot

That was after I closed out bioshock but you see one GPU as around 80% and the other nothing

 

[Maziar]

Hello and welcome to the forums mate
Do u get low FPS too ? when u use DX10 ?
Also did u have SP1 first ? if so then did u have this problem ?

 

[50bmg]

i am sorry if i am stating the obvious, but make sure you CF bridge is installed and make sure Catalyst AI is running in the CCC. Crossfire will not run if the Disable box is checked in CCC.

 

[blu9987]

I have the internal crossfire connector on my cards and catalyst AI on standard. The thing is crossfire on my computer works in directX9 but not directx10. For instance if I load crysis warhead in dx9 crossfire logo appears and GPU-Z shows both cards having load, if i load it in dx10 it doesnt appear and one of them has nothing.

@maziar: I have not tried sp1 as I installed sp2 before I got my 2nd graphics card. In some games I get rather low fps in dx10 but I haven't played that many that support it.

 

[Maziar]

Do u have the latest Catalyst driver installed ? if not then install it,if yes then roll back to an older driver and test with it

 

[blu9987]

i've tried the latest catalyst 9.6 as well as 9.2 and a modified version of 8.6 with no luck.

 

[Maziar]

Can u try with VISTA SP1 ?

 

[Twoboxer]

Curious: Are both of your 3870's same make/model? I was wondering if this or something similar was involved in this unusual problem:

1 ATI Radeon HD 3870 GPUs support PCIe 2.0. Some third party board configurations may not fully comply with complete PCIe 2.0 specification and operate at PCIe 1.1 specifications on motherboards that support PCIe 2.0 . Please consult with board manufacturer if this is an important feature for you.

 

[blu9987]

Curious: Are both of your 3870's same make/model?

No :/
One is a Diamond 512mb DDR4 HD3870 one is a Sapphire 512mb DDR4 HD3870.

 

[Twoboxer]

Compare the specs - maybe there's something there? We'd of course be looking for something that stops DX10.

 

[blu9987]

Can u try with VISTA SP1 ?

I'll partition my drive and install vista again with just sp1 later tonight, though I'm not looking forward to it xD


@Twoboxer - They both are DX10 compatible and work separately, just crossfire wont initiate in dx10 games 🙁
here are my two cards:
http://www.diamondmm.com/3870PE4512.php
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=3747342&CatId=3670

the sapphire one was an after thought I was buying ram a year after i built my pc and figured might as well hook up a 2nd card.

 

[blu9987]

I think I found out whats wrong...

is there supposed to be TWO internal connectors? I only have one... I just saw a youtube video and it shows 2 cards and 2 ati crossfire bands going across.

 

[Maziar]

Well u can CrossFire your cards with only 1 CrossFire bridge,its recommended to use 2 but it will work with 1 bridge too

 

[blu9987]

Well u can CrossFire your cards with only 1 CrossFire bridge,its recommended to use 2 but it will work with 1 bridge too

so that doesn't really matter then huh? :/

does it matter which of the two slots I put the single bridge and/or what direction i plug it in (I can plug it on 2 ways Crossfire reading upside down or rightside up)

 

[Twoboxer]

What happens when you try that?