[.25 BTC Bounty] Cannot use more than 3 cards on GigaByte motherboard

[joshv06]

I cannot get 4 cards working with 1x risers or 4 cards working at all for that matter. I have never POSTed with 4 cards plugged in.

Specs:

GIGABYTE GA-990FXA-UD5 AMD AM3+ 990FX Motherboard
R9 290 Video Cards
Enermax Revo 1500W PSU
8GB Ram

Works when:

3 cards plugged directly work
1 card with PCI-E 1x riser in 1x port works
3 cards in PCI-E 16x slots with 16x risers work


I get black screen (no POST) when:
Using 2 cards directly plugged in and the other 2 in 16x risers.

I live in Houston Texas and have a setup here at home. I will give .6 btc if anyone wants to come and try a solution.

[coin123123]

now enough watt.
try to power two cards from second psu.

[woutersteven]

PSU issue, use a 2nd PSU and make sure you short the plug on the 2nd PSU otherwise it wont work. http://www.overclock.net/t/15751/info-can-i-use-two-power-supplies-with-one-computer

[dE_logics]

WOW MAN WOW!!!! 

What OS?

[dE_logics]

Oh, and you saw this?

https://litecointalk.org/index.php?topic=2702.915

[joshv06]

Wouldn't 1500W be enough for 4 R9 290's? I used to run a full system with fans, 2 hdd's, 4x 7970s on an Enermax 1350W.

Also, I made powered risers. They work, but it's the same thing. I can't get 4 cards at once to work.

My board does not require shorting the a/b pins. The 1x riser works.

[vm1990]

this might sound strange but crossfire the card in the x1 slot to the 1st card in the 1st x16 slot

1500w should be more than enough for these configurations

[Cascaders28]

What BIOS version are you using?

I think you'll actually need to make sure CF is off in the BIOS and you're not using any bridges for this board to support more than 3 cards. That is where my mind starts at least...

[af_newbie]

Wouldn't 1500W be enough for 4 R9 290's? I used to run a full system with fans, 2 hdd's, 4x 7970s on an Enermax 1350W.

Also, I made powered risers. They work, but it's the same thing. I can't get 4 cards at once to work.

My board does not require shorting the a/b pins. The 1x riser works.

I run three R9 290x with 1200W PSU and I put the 4th card on 450W second PSU.
All four are on powered risers.  I'm using the same motherboard, default BIOS settings, Sempron 145 CPU, SSD drive.

[Trini8ed]

Wouldn't 1500W be enough for 4 R9 290's? I used to run a full system with fans, 2 hdd's, 4x 7970s on an Enermax 1350W.

Also, I made powered risers. They work, but it's the same thing. I can't get 4 cards at once to work.

My board does not require shorting the a/b pins. The 1x riser works.

Have you tried a different board? Maybe the single board you are testing on isn't functionally correctly, I'd try another board.

[undeadbitcoiner]

Wouldn't 1500W be enough for 4 R9 290's? I used to run a full system with fans, 2 hdd's, 4x 7970s on an Enermax 1350W.

Also, I made powered risers. They work, but it's the same thing. I can't get 4 cards at once to work.

My board does not require shorting the a/b pins. The 1x riser works.

I run three R9 290x with 1200W PSU and I put the 4th card on 450W second PSU.
All four are on powered risers.  I'm using the same motherboard, default BIOS settings, Sempron 145 CPU, SSD drive.

!
+1

Did you tried changing motherboard? I dont thisk its issuee with PSU

[Boxman90]

TDP is 275 for a R9 290, so the PSU has plenty of power.

I'm running 4 GPU's on my GigaByte motherboard. I use 1x risers on all cards.

What might be the key is running the presence mod on all PCI-e slots



It's what I needed to get my 4x GPU running and detected.

Otherwise, I can confirm that with the presence mod, the Gigabyte 990FXA-GD65 works on 4 GPU's (with some GPU's in the 1x slots, all slots on presence mod. Even the 16x slots). The GD65 also has the great extra power plug near the PCI-e slots.

Yes, you might not heed the a/b shorting mod with one card in the 1x slot and nothing for the rest, same with me. But with 4 cards, it was MANDATORY to do the mod on _all_ slots, even the 16x ones. Otherwise it did not work for me either.

I used thin paperclips bent into shape with some pliers.

Good luck, and look forward to the bounty.

1427iTKC5ygVBqeFjMj6YRkB9dtRnAgZA7

[woutersteven]

According to this benchmark: http://www.techspot.com/review/736-amd-radeon-r9-290/page8.html, the R9 290 takes 350 watts.

Four cards would be 1400 Watts, add 125 watt for the cpu and the rest of the system and you're at 1525 Watt. A 1500 Watt PSU at 80% gives at most 1200 watts reliably, so perhaps one PSU wouldn't be enough to handle the load. However this is at 100% load, which it will never reach during POST sequence.

[Boxman90]

According to this benchmark: http://www.techspot.com/review/736-amd-radeon-r9-290/page8.html, the R9 290 takes 350 watts.

Four cards would be 1400 Watts, add 125 watt for the cpu and the rest of the system and you're at 1525 Watt. A 1500 Watt PSU at 80% gives at most 1200 watts reliably, so perhaps one PSU wouldn't be enough to handle the load. However this is at 100% load, which it will never reach during POST sequence.

1500W is the power it will provide on the 12v side. With 80% efficiency it'll draw about 1875 Watts from the socket.

Modern PSU's have no problem providing top power 100% of the time. My mining rigs are stable for many months at 24/7 100% PSU load (1200W on a 1250W Seasonic PSU).

Power is really not the issue. CPU doesn't draw 125 Watt either, as all you need is the cheapest dualcore you can find.

[woutersteven]

1500W is the power it will provide on the 12v side. With 80% efficiency it'll draw about 1875 Watts from the socket.

Modern PSU's have no problem providing top power 100% of the time. My mining rigs are stable for many months at 24/7 100% PSU load (1200W on a 1250W Seasonic PSU).

Power is really not the issue. CPU doesn't draw 125 Watt either, as all you need is the cheapest dualcore you can find.

I stand corrected, thanks I didn't know it was measured on the 12v side.

[Boxman90]

We're all here to learn

[dE_logics]

Regardless, the cards should be detected when they're not in use.

If you use Linux, I can help.

[joshv06]

TDP is 275 for a R9 290, so the PSU has plenty of power.

I'm running 4 GPU's on my GigaByte motherboard. I use 1x risers on all cards.

What might be the key is running the presence mod on all PCI-e slots



It's what I needed to get my 4x GPU running and detected.

Otherwise, I can confirm that with the presence mod, the Gigabyte 990FXA-GD65 works on 4 GPU's (with some GPU's in the 1x slots, all slots on presence mod. Even the 16x slots). The GD65 also has the great extra power plug near the PCI-e slots.

Yes, you might not heed the a/b shorting mod with one card in the 1x slot and nothing for the rest, same with me. But with 4 cards, it was MANDATORY to do the mod on _all_ slots, even the 16x ones. Otherwise it did not work for me either.

I used thin paperclips bent into shape with some pliers.

Good luck, and look forward to the bounty.

1427iTKC5ygVBqeFjMj6YRkB9dtRnAgZA7

I have tried this. Shorting the 1x slot with a card on a 1x riser while the other 3 cards are plugged directly in. Same problem.

No POST. I also tried putting the HDMI cable in each card while booting.

Also some notes:

Booting the card from a 1x slot with a 1x riser with and without shorting the A/B pins works perfectly.

[Boxman90]

TDP is 275 for a R9 290, so the PSU has plenty of power.

I'm running 4 GPU's on my GigaByte motherboard. I use 1x risers on all cards.

What might be the key is running the presence mod on all PCI-e slots



It's what I needed to get my 4x GPU running and detected.

Otherwise, I can confirm that with the presence mod, the Gigabyte 990FXA-GD65 works on 4 GPU's (with some GPU's in the 1x slots, all slots on presence mod. Even the 16x slots). The GD65 also has the great extra power plug near the PCI-e slots.

Yes, you might not heed the a/b shorting mod with one card in the 1x slot and nothing for the rest, same with me. But with 4 cards, it was MANDATORY to do the mod on _all_ slots, even the 16x ones. Otherwise it did not work for me either.

I used thin paperclips bent into shape with some pliers.

Good luck, and look forward to the bounty.

1427iTKC5ygVBqeFjMj6YRkB9dtRnAgZA7

I have tried this. Shorting the 1x slot with a card on a 1x riser while the other 3 cards are plugged directly in. Same problem.

No POST. I also tried putting the HDMI cable in each card while booting.

Also some notes:

Booting the card from a 1x slot with a 1x riser with and without shorting the A/B pins works perfectly.

Just for shits 'n giggles, put them all on 1x risers and short all 4 slots?

I mean, at my Gigabyte board one card on a 1x riser in a 1x slot works fine too. All 4 at once caused the problem. Just try it mate.

[joshv06]

Will try that