Can Gigabyte GA-870A-UD3 support 2 GPU?

[goldbit]

A newbie question.

My Mobo is Gigabyte GA-870A-UD3 running a sapphire 6870.

From the manual:

1 x PCI Express x16 slot, running at x16 (PCIEX16) 1 x PCI Express x16 slot, running at x4 (PCIEX4) Note: The PCIEX1_1 and PCIEX1_2 slots share bandwidth with the PCIEX4 slot. When PCIEX4 slot is populated with a x4 card, the PCIEX1_1 and PCIEX1_2 slots become unavailable


I am a little confused. Will this motherboard allow me to add one more GPU for mining?

Thanks in advance!

[BTCPrizes]

It looks and sounds as this board has 2 PCI-e slots? From what I've gathered you have 1 card in it now?

You should be able to fit 2 as long as they physically fit!

Confirm that you have 2 identical PCI-e slots and you're good to go.

[goldbit]

It looks and sounds as this board has 2 PCI-e slots? From what I've gathered you have 1 card in it now?

You should be able to fit 2 as long as they physically fit!

Confirm that you have 2 identical PCI-e slots and you're good to go.

Thanks for your reply.

Yes. I only have 1 card now.

The part I am confused is that it says 1 PCI-e 16x, and the other PCI-e is 4x.

What is the difference between PCI-e 16x and PCI-e 4x?

Sorry for newbie question

[emugoo]

you munged up the specs, so i looked it up:

1 x PCI Express x16 slot, running at x16 (PCIEX16)
1 x PCI Express x16 slot, running at x4 (PCIEX4) (Note 3)
2 x PCI Express x1 slots (The PCIEX1_1 and PCIEX1_2 slots share bandwidth with the PCIEX4 slot.) (Note 3)
      (All PCI Express slots conform to the PCI Express 2.0 standard.)
3 x PCI slots

(Note 3) The PCIEX1_1 and PCIEX1_2 slots share bandwidth with the PCIEX4 slot. When PCIEX4 slot is populated with a x4 card, the PCIEX1_1 and PCIEX1_2 slots become unavailable.

It sounds as if you'd be restricted to 4x on the second slot. Also, you should not have anything on the smaller "pci-x 1" slots, because those will not work at all when using slot 1 and 2. unless you added a wifi or tv decoder card to the 1x pci-x slots, then that should not concern you.

No idea how the 4x speed changes the mining behaviour tho. Does mining need a lot of i/o bandwidth? If yes, then you could be restricted by the reduced speed, if not, then go ahead.

[goldbit]

you munged up the specs, so i looked it up:

1 x PCI Express x16 slot, running at x16 (PCIEX16)
1 x PCI Express x16 slot, running at x4 (PCIEX4) (Note 3)
2 x PCI Express x1 slots (The PCIEX1_1 and PCIEX1_2 slots share bandwidth with the PCIEX4 slot.) (Note 3)
      (All PCI Express slots conform to the PCI Express 2.0 standard.)
3 x PCI slots

(Note 3) The PCIEX1_1 and PCIEX1_2 slots share bandwidth with the PCIEX4 slot. When PCIEX4 slot is populated with a x4 card, the PCIEX1_1 and PCIEX1_2 slots become unavailable.

It sounds as if you'd be restricted to 4x on the second slot. Also, you should not have anything on the smaller "pci-x 1" slots, because those will not work at all when using slot 1 and 2. unless you added a wifi or tv decoder card to the 1x pci-x slots, then that should not concern you.

No idea how the 4x speed changes the mining behaviour tho. Does mining need a lot of i/o bandwidth? If yes, then you could be restricted by the reduced speed, if not, then go ahead.

I plan to run 2 x HD 6870 (add one more) on this machine. I wonder what will be speed of the 2nd card if it is plugged into the PCIEX4 slot.

[BiafraRepublic]

Generally speaking, the perceived speed on the card in the PCIeX16 slot running at x4 would be one-fourth of normal due to the reduced throughput.