Gigabyte GA-990FXA-UD5, Finally got it stable with 6 cards
Lots of problems with the mobo at first, some cards would work with 1x extenders and some wouldn't and never got it to detect 6 cards at the same time. Ended up solving it by shorting A1 to B17 in the 16x_2 and 8x slot and it seems to have fixed it (16x_1 slot might have to be shorted as well but got a card in that slot that seems to work in any motherboard and slot no matter what, pins are shorted on the card itself perhaps?) 4x and 1x slots working by default. Using flexible 1x extenders in all slots.
Topic: List of motherboard that require shorting pin A1 B17 for pci-e 1x to work. - page 7. (Read 99826 times)
April 11, 2012, 04:37:26 PM
February 24, 2012, 06:07:39 PM
Asus P5Q-E, both PCIe x1 slots require shorting A1 with B17 pins (unless you hot plug the GPU but then it doesn't always work for some reason)
extenders I use are not powered and are 19cm if this information is of any use for you
extenders I use are not powered and are 19cm if this information is of any use for you
February 19, 2012, 10:11:40 AM
I thought I would add to this thread - the motherboards listed that require shorting simply support PCIe hot plug card detection, they are not doing anything wrong. What is doing something wrong is the 16x-1x adapter.
I thought I would investigate whether the video card should be connecting all available hotplug pins (there is one at 1x, 4x, 8x, and 16x card length). The highlighted section of the PCISIG spec says cards should only short the last hotplug detect pin back to hotplug ground. Therefore we can conclude that 16x=>1x adapter cables should ideally have been designed to connect all PRSNT2# lines on the 16x connector together (B81, B48, B31, B17) to pass any width card's hotplug signal through to the 1x detect line.
As you can see in the diagram below, PRSNT2# only detects if it has been grounded, B17 (the pin for 1x cards) can be shorted to B16 or B18 for ground as mentioned by Zoomer. The A1 hotplug ground has a shorter finger pad; this along with a short finger hotplug detect at the other end of the complete card length ensures the card is fully inserted before the hotplug signal is connected. The PCIe 1x adapter should likewise have a shorter B17 finger on the card that plugs into the mainboard.
I thought I would investigate whether the video card should be connecting all available hotplug pins (there is one at 1x, 4x, 8x, and 16x card length). The highlighted section of the PCISIG spec says cards should only short the last hotplug detect pin back to hotplug ground. Therefore we can conclude that 16x=>1x adapter cables should ideally have been designed to connect all PRSNT2# lines on the 16x connector together (B81, B48, B31, B17) to pass any width card's hotplug signal through to the 1x detect line.
As you can see in the diagram below, PRSNT2# only detects if it has been grounded, B17 (the pin for 1x cards) can be shorted to B16 or B18 for ground as mentioned by Zoomer. The A1 hotplug ground has a shorter finger pad; this along with a short finger hotplug detect at the other end of the complete card length ensures the card is fully inserted before the hotplug signal is connected. The PCIe 1x adapter should likewise have a shorter B17 finger on the card that plugs into the mainboard.
February 19, 2012, 08:24:14 AM
Without this page i would have been lost long time ago
adding mine:
ASUS M4A88T-V EVO/USB3
adding mine:
ASUS M4A88T-V EVO/USB3
November 24, 2011, 03:15:00 PM
ASUS P5N-T needs this mod also.
(On both x1 -> x16 in x16 and in x1 slot)
(On both x1 -> x16 in x16 and in x1 slot)
September 30, 2011, 07:24:53 AM
ASROCK N7AD-SLI requires this mod.
September 24, 2011, 03:49:00 PM
RESOLVED:
I've switched to regular x1 -> x16 ribbon riser and switched from Windows 7 to BAMT. With this, Foxconn A7DA-S 3.0 is nicely mining using 3 cards (2 directly in PCIE x16, 1 in PCIE x1 using riser) *without* shorting any pins.
I've switched to regular x1 -> x16 ribbon riser and switched from Windows 7 to BAMT. With this, Foxconn A7DA-S 3.0 is nicely mining using 3 cards (2 directly in PCIE x16, 1 in PCIE x1 using riser) *without* shorting any pins.
September 21, 2011, 03:27:27 AM
Hey,
testet on a Gigabyte MA770 ud3 and the only shortening you need is in the 16x Slot if using an 1x riser there.
The 1x slots with 1x riser work without.
My setup:
3* 1x->16x Rrser in 1x slot
1* 1x->16x riser in 16x slot (with shortening)
Useer
testet on a Gigabyte MA770 ud3 and the only shortening you need is in the 16x Slot if using an 1x riser there.
The 1x slots with 1x riser work without.
My setup:
3* 1x->16x Rrser in 1x slot
1* 1x->16x riser in 16x slot (with shortening)
Useer
September 17, 2011, 03:41:48 PM
It is Foxconn A7DA-S 3.0.
I can't say for sure whether the port is physically damaged or is it just software issue. On the other machine with the same mobo, there are periods of time when sometimes card is working, sometimes system gets unstable (freezes), but the card is being detected and sometimes card is not being detected at all - I haven't noticed any rule to it though.
I have absolutely no problem on mine, I even wonder if it require the mod I think I had problem because of a bad card.I can't say for sure whether the port is physically damaged or is it just software issue. On the other machine with the same mobo, there are periods of time when sometimes card is working, sometimes system gets unstable (freezes), but the card is being detected and sometimes card is not being detected at all - I haven't noticed any rule to it though.
I used for a while the two yellow slot one in-between without the mod, I suggest you try them as-is. And check all card alone one at the time.
I only send power through the extender at the 5th GPU.
September 17, 2011, 01:51:57 PM
It is Foxconn A7DA-S 3.0.
I can't say for sure whether the port is physically damaged or is it just software issue. On the other machine with the same mobo, there are periods of time when sometimes card is working, sometimes system gets unstable (freezes), but the card is being detected and sometimes card is not being detected at all - I haven't noticed any rule to it though.
I can't say for sure whether the port is physically damaged or is it just software issue. On the other machine with the same mobo, there are periods of time when sometimes card is working, sometimes system gets unstable (freezes), but the card is being detected and sometimes card is not being detected at all - I haven't noticed any rule to it though.
September 16, 2011, 08:15:25 PM
Shorting A1-B17 worked on Foxconn (card was detected and running). However after running for 12 hours it seems like the PCIE slot on mobo died. I tried using the second port but apparently it died too shortly after.
I was running total of 3 5830 cards on Foxconn (overclocked from 800 to 900). Is it possible that the card was draining too much power from PCIE x1 which caused it to get damaged?
When you run cards on PCIE x1 do you also redirect A2,A3,B1,B2,B3 pins to use 12V directly from PSU isntead of mobo?
First of ,,, WHAT foxconn ? It was only causing stability problem on mine. A7DA... I was running total of 3 5830 cards on Foxconn (overclocked from 800 to 900). Is it possible that the card was draining too much power from PCIE x1 which caused it to get damaged?
When you run cards on PCIE x1 do you also redirect A2,A3,B1,B2,B3 pins to use 12V directly from PSU isntead of mobo?
September 15, 2011, 11:37:01 AM
Shorting A1-B17 worked on Foxconn (card was detected and running). However after running for 12 hours it seems like the PCIE slot on mobo died. I tried using the second port but apparently it died too shortly after.
I was running total of 3 5830 cards on Foxconn (overclocked from 800 to 900). Is it possible that the card was draining too much power from PCIE x1 which caused it to get damaged?
When you run cards on PCIE x1 do you also redirect A2,A3,B1,B2,B3 pins to use 12V directly from PSU isntead of mobo?
I was running total of 3 5830 cards on Foxconn (overclocked from 800 to 900). Is it possible that the card was draining too much power from PCIE x1 which caused it to get damaged?
When you run cards on PCIE x1 do you also redirect A2,A3,B1,B2,B3 pins to use 12V directly from PSU isntead of mobo?
September 13, 2011, 07:44:42 PM
Actually, looking at the pinout, shorting B17 to either B16 or B18 should work. Just disconnect the thing from the motherboard if you don't have anything connected.
September 07, 2011, 10:44:21 PM
He said B1-A17. The right pins are A1-B17.
If you can't pay attention to these details, maybe you shouldn't even be trying to short them
If you can't pay attention to these details, maybe you shouldn't even be trying to short them
September 07, 2011, 08:49:51 PM
Note to self : shorting B1 with A17 will destroy the slot, but not the card. 
wait, what? I was just trying to short these pins and now you guys re telling me it'll fry my board? so whats the point of this thread?
September 07, 2011, 12:27:44 PM
Note to self : shorting B1 with A17 will destroy the slot, but not the card.
September 02, 2011, 12:20:36 AM
Foxconn A7DA-S 3.0 had some crazy behavior with the 4th GPU,
The mod seems to have fixed it. (first slot)
The mod seems to have fixed it. (first slot)
August 27, 2011, 01:22:52 PM
ASUS A8N32-SLI too.
August 26, 2011, 03:12:58 AM
ECS P45T-A requires it, but the board also got toasted after a few days, so I wouldn't suggest it. 
It failed for another reason. Pins A1-B17 are meant to be shorted. Perhaps you pulled too much current on the motherboard's 12V rail.
August 26, 2011, 12:23:06 AM
Anyone know if this trick works with asus P5EVM-HDMI
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