Can anybody please tell me how to get more than 3 GPU cards to work on a Gigabyte GA-990FXA-UD5. I have two identical setups both with the same problem that has given me shit for months.
AMD X2-260 CPU
4 GB Ram 1333
Corsair 1200 w PSU
5850 GPU x 8 (4 for each board)
Using:- CGMiner 2.3.2 , 11.6 Drivers and SDK 2.4 on Xubuntu 11.04 64b. This is a full install on a HDD. According to everything I have read, that setup should go well,
but not so!!
Both boards can run 3 x 5850‘s straight off the slots ie PCIE x16_1 , PCIE x 16_2 & PCIE x 8.
By substitution I know that all the cards and the extender cables work properly. The interesting thing is that if you plug the cards into those slots used previously direct, but now using the Extender cables the board will only see the card in PCIE x16_1 It will not recognise the cards in PCIE x 16_2 & PCIE x 8 with the extender cables. It will however recognise the the second two of the cards if the extenders are plugged to PCIE x 4 _1 & PCIE x 4 _2. Thus giving again a total of 3 cards recognised.
I have done (ad infinitum) the “sudo aticonfig --initial --adapter=all” with all sorts of variations on the -f. and a few of the Fxxck but it does not make any difference.
To me as a Linux and AMD noob it looks like an issue of Latency with the PCIE slots. I have looked thru the Bios (current F8) and cannot see any way to adjust PCIE latency although I have seen references in other posts to figures like “64 adjusted up to 96“ but nothing specific.
Or is it simply that these motherboards will only allow PCIE 3 slots at any one time?
Has anybody had success with 4 or more cards on the GA-990FXA-UD5 or have I bought two pieces of junk?
The only thing that has worked thru all this is Clonezilla, what a Godsend to image discs
Edit:- the extender cables are 16 x 16 with Molex power
Edit:- 13th June, tested with four 1 x 16 powered extenders on all slots, still not able to get FLRGX to see more than 3 cards no matter what!!