Gigabyte MA790GP-DS4A: PCI-E slot x8 not working

[brice3010]

I have a set up with a Gigabyte mobo MA790GP-DS4H, a AMD 9850BE, 2x 1Gb 1066MHz memory, 1x WD Velociraptor 150Gb, 3x Samsung 1Tb and 2x Gigabyte HD4850 graphics cards to be set-up in Crossfire.

So far I received 3 (THREE!!!!!!) new mobo's from the shop, and it is impossible to get any output from a card inserted in PCI-E slot x8 (the lower vga slot). Not with bios in standard setup, not with the onboard vga disabled, and not in any of the four possible bios graphics settings (PCI slot, OnChipVGA, PEG or PEG1). Not with any of both vga cards. Both cards DO work when inserted in the (upper) PCI-E slot x16.

I have been in touch witht he Gigabyte forum on Tweak Town forums and with AMD/ATI about their Crossfire (although this definitely seems to be a mobo issue), but they have not been able to pinpoint anything I might have to do to solve this issue. Not with drivers, not with a bios flash, not with bios settings, ....

Is Gigabyte now shipping mobo's with non-functional items????

 

[danbfree]

I have the same mobo but not into mulit-GPU's... yet. That sucks to hear as adding a second 4850 was a possibility. From what it looks like an extensive BIOS update is overdue but otherwise I really like my board. I just had to disable the onboard audio on the video card to get rid of high idle CPU use.

 

[bilbat]

I'm frankly amazed that no one at TweakTown pointed this out, but Xfire only works on Intel/ATI hardware; AMD/nVidia uses SLI exclusively. Slots should work, but you've got to omit the Xfire bridge connector...

 

[brice3010]

Problem solved. Very strange, but inserting a brandnew GT8800 in the second slot suddenly gave me a display!!!!! Then I inserted the HD4650 (not 4850 as I mistakenly wrote above) in the second slot, and I have display too!!!!!! Then the first slot with the other HD4650, and I have crossfire!!!!!!

I can't find any logic. AMD/ATI helpdesk baffled too, they wrote me a new driver is neing released shortly preventing this type of problem.

 

[brice3010]

I tried to edit my message, but I can't; the vga boards ARE hd4850.... not hd4650