The electrical isn't the issue. I have dedicated 20-amp circuits for each rig. So, 2 750 watt PSUs plugged into a single surge protector plugged into a 20-amp circuit... On 5 total different circuits. The power is fine; that's not the issue at all.

Again, exactly similar hardware setup for all of them. Something is different in that one is able to push those good numbers whereas all the others fail at it.

Hello everybody,

BOUNTY FOR SOLUTION: .02 BTC

I'm writing because I have 5 rigs. The specs are below:

6x r9 270 GIGABYTE GV-R927OC-2GD
Celeron G1620
3 Powered Risers, 3 Unpowered
MSI Z77A-GD65
4GB RAM
32GB SSD
2x EVGA Supernova 750 Watt Power Bronze Certified Power Supply (Daisychained)
Windows 8.1

So here's my issue:

On one of the rigs, I've been able to get 6 of the cards running at about 2.858MH/S. That's about 475-477 KH/s per card on that rig.

The hardware setups for these rigs are absolutely identical in every way.

However, on the rest of the 5 rigs, the rigs crash if I use the exact same settings I'm using for the one rig... The graphics will either become completely unstable, or the rig will freeze, or a GPU in the rig will go sick/dead. I can't use the same settings I use on the one rig in the other rigs to get that nice high 475KH/s rate.

I'm worried that maybe I changed something in the software on Windows that gives me these rates on the one system but I didn't do it on all the others; can't figure out what they might be though.

The settings I'm using for the hashrate that's working on the one rig are as follows:


Why does this work on one rig and not the others? They start out fine and then crash, while this one stays stable!

Solution must work in Windows 8.1 and give a relatively similar hashrate to qualify for bounty.

I can also do Teamviewer for diagnosis.

I just wanted to provide an update for those who might be having a similar problem. The provided solutions didn't solve the issue for me, but I wound up plugging the last card directly into the final 16X slot on the motherboard and moving the middle riser out of the middle 16X slot (only populate 16X 1 and 16X 3), and that allowed the system to recognize all 6 of the cards.

djcrypto, I already disabled the non-essentials and that didn't solve the issue.

forcefedvr6 Do you have the MSI Z77A-GD65? I've seen it written all over that this board doesn't require jumpers. But perhaps that's what I need to try; please let me know if you have this board and if that's what solved your issue. Thanks!

Hello, Duane. Yes, it's the 64-bit version.

Morbid, that's not true. I have 6 cards running on Gigabyte boards in other rigs.

I posted this in another thread and didn't get a solution so I'm posting it here with a bounty of .02 BTC so that I can get a quick solution.

To start, and to clear some things up because some will ask:

1) It's not a code 43 error. The GPU is not showing up in Windows, period.
2) It's not a faulty riser, or a faulty card. This same problem is occurring in 5 different rigs with exactly similar components.
3) Windows is not seeing the 6th card at all. 5 cards are recognized and installed as R9 200 Series and are functioning/hashing normally.
4) Yes, I have tried the deep uninstall methods.
5) Yes, I have tried the custom drivers for 7-card rigs.

Something is going on with Windows, the motherboard, the BIOS, or the power supplies that the 6th card is not recognized. The fans are spinning on all cards. All cards are plugged in.

The stipulations on the bounty are as follows:

a) The solution must enable me to hash with all 6 cards simultaneously.
b) The solution must apply to Windows 8.1 I need to use Windows for Teamviewer, ease of use, etc.

Hope to hear from you guys soon.

My problem is that I just built 5 rigs that are 6 cards each, but despite several settings alterations, I can't get the rigs to recognize 6 cards (only 5).

Here are my rig specs:

MSI Z77A-GD65 Motherboard
6 Risers (3 powered, 3 unpowered) 1X to 16X
2X 750 Watt EVGA Supernova PSU Daisychained
6X Gigabyte R9 270 OC
Celeron G1620
4GB RAM
32GB SSD
Windows 8.1

Risers are plugged into all ports except the last 16x port on the board (the 7th and final port). I have tried switching risers around a bit to ignore one of the two 1x slots that are next to each other, and plug into the final 16x port, but that was also a no-go.

I've changed a few settings in the BIOS, but maybe I'm missing the important one.

Only 5 cards show up in Windows. Not 5 with the 6th with an exclamation point, just 5 period.

Please help me fix this, as I have 5 rigs, each without the 6th card working. It's very frustrating, but has at least helped me determine that it's not the cards or the risers. Something with windows or the motherboard.

Thanks a lot in advance, guys.

I posted this in another thread and didn't get a solution so I'm posting it here with a bounty of .02 BTC so that I can get a quick solution.

To start, and to clear some things up because some will ask:

1) It's not a code 43 error. The GPU is not showing up in Windows, period.
2) It's not a faulty riser, or a faulty card. This same problem is occurring in 5 different rigs with exactly similar components.
3) Windows is not seeing the 6th card at all. 5 cards are recognized and installed as R9 200 Series and are functioning/hashing normally.
4) Yes, I have tried the deep uninstall methods.
5) Yes, I have tried the custom drivers for 7-card rigs.

Something is going on with Windows, the motherboard, the BIOS, or the power supplies that the 6th card is not recognized. The fans are spinning on all cards. All cards are plugged in.

The stipulations on the bounty are as follows:

a) The solution must enable me to hash with all 6 cards simultaneously.
b) The solution must apply to Windows 8.1 I need to use Windows for Teamviewer, ease of use, etc.

Hope to hear from you guys soon.

My problem is that I just built 5 rigs that are 6 cards each, but despite several settings alterations, I can't get the rigs to recognize 6 cards (only 5).

Here are my rig specs:

MSI Z77A-GD65 Motherboard
6 Risers (3 powered, 3 unpowered) 1X to 16X
2X 750 Watt EVGA Supernova PSU Daisychained
6X Gigabyte R9 270 OC
Celeron G1620
4GB RAM
32GB SSD
Windows 8.1

Risers are plugged into all ports except the last 16x port on the board (the 7th and final port). I have tried switching risers around a bit to ignore one of the two 1x slots that are next to each other, and plug into the final 16x port, but that was also a no-go.

I've changed a few settings in the BIOS, but maybe I'm missing the important one.

Only 5 cards show up in Windows. Not 5 with the 6th with an exclamation point, just 5 period.

Please help me fix this, as I have 5 rigs, each without the 6th card working. It's very frustrating, but has at least helped me determine that it's not the cards or the risers. Something with windows or the motherboard.

Thanks a lot in advance, guys.