List of motherboard that require shorting pin A1 B17 for pci-e 1x to work.

[lucita777]

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?

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[Transisto]

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...

[lucita777]

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.

[Transisto]

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 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.

[Useer]

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

[lucita777]

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.

[MiningBuddy]

ASROCK N7AD-SLI requires this mod.

[ocminer]

ASUS P5N-T needs this mod also.

(On both x1 -> x16 in x16 and in x1 slot)

[SaintFlow]

Without this page i would have been lost long time ago

adding mine:

ASUS M4A88T-V EVO/USB3

[deepceleron]

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.

[malevolent]

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

[rograz]

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.

 

[ModusPwnd]

• MSI 890FXA-GD70 AM3

Also the MSI 990FXA-GD80 needs it.  I presume this is a successor to the 890.  I just got the 990 and tried the fix and it worked.  My x1 slots were not working before the fix either, but after the fix bot the x1 and x16 slots worked.

Now I have a few more ribbons to solder... I see the suggestion of shorting with B18 because B17 simply needs to see ground.  And seeing ground always will be ok for the mobo (is that so?).  For ease of soldering tomorrow I will solder B17 to a molex connector.  That should be just as good right?  My ribbons have molex power supplies to the 5 power wires so each ribbon has a free ground on the molex for me to use.

[dropt]

• Asus - P7P55D-E Pro

[ssateneth]

EVGA 790i SLI Ultra needs shorting on 1x and 16x slots.

[flatronw]

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.

 

I realise this post is a bit dated but I hope the OP will see it.

I would really appreciate some more detail here. I have two of these Gigabyte GA-990FXA-UD5 boards and I am damned if I can get anymore than 3 5850's working on each board. Each board acts exactly the same. That is after trying all of the above and anything else that I can think of.  ie 16 -> 16 extenders 1 -> 16 extenders powered and non powered, jumpers and no jumpers. It simply will not see the cards in the "lspci" command.

Specifically what version of the Gigabyte GA-990FXA-UD5 are you talking about and which version of Bios are you using?? I have the current Bios Version F8 installed. My board is marked as "V 1" ie it is the version that came preflashed for the AMD Bulldozer chip whereas I believe the earlier boards did not. I am starting to wonder if there may have been other changes made as well

I am trying to use Xubuntu 11.04 64b, SDK 2.4 with 11.6 drivers and CGMiner 2.3.2 -4.2.

Thanks

[ajstar]

Do I need this shortcut trick to plug card into full 16x slot with only 1x to 1x riser on my 890FXA? I guess so (to let mobo know that it can use just 1x mode) but you know better to be safe then soory so I am asking first

[multi#lord]

Shouldn't this thread be transformed into a wiki (and organized by platform/socket)? Probably be little easier to find a specific board/cpu/manufacturer, just an idea  .

EVGA P55 Micro:

-x1 needs shorting, and powered riser; unstable when booting into Win 7 64 (using a 6850 or a 7970)
-Legacy PCI slot with riser to PCIE x16 and a powered riser makes system unstable and locks, won't reach Win 7 64 login.

[Transisto]

Shouldn't this thread be transformed into a wiki (and organized by platform/socket)? Probably be little easier to find a specific board/cpu/manufacturer, just an idea  .

EVGA P55 Micro:

-x1 needs shorting, and powered riser; unstable when booting into Win 7 64 (using a 6850 or a 7970)
-Legacy PCI slot with riser to PCIE x16 and a powered riser makes system unstable and locks, won't reach Win 7 64 login.

Wiki, Well I'm trying to update OP with new board contribution.

Are you sure you need powered extender for, what 2-3 cards ?  It is recommended when going 5 gpu and above.

[pekv2]

I am going to be testing out my pcie x 1 slot with an adapter & a card.

Would any type of overclocking while using the pcie x 1 slot, fry the pcie x 1 slot and/or the gfx card?

What are you guy's thoughts?

I am taking extreme caution before preceding.

Of course, this question is for the slot being shorted and not shorted.