Bitcoin Forum

Hello to everyone!

First of all, I'm a noob in Mining and such, so I'm sorry if I'm asking something obvious for you.

That sayd, I've some problems with my mining rig, here my setup:

MB: Asrock 970 Extreme4
CPU: Sempron 145
PSU: Corsair AX860 Platinum
RAM: Gskill 1x4Gb 1333Mhz
SSD: Kingston 60Gb
GPU: 3x Sapphire R9 280x OC Dual-X 3GbGDDR5
Riser: 3x Powered Risers 1x-16x

I tested all the 3 cards and all the 3 risers in every combination, and all of the items are working good at 700-750 KH/s.


My problem is the following:

The PCIE4 slot, the 16x in the middle of the MB, is not recognizing any card if I use them with any of the risers -> D6 error on the Dr.Debug led on the MB, that is: "No console output devices are found".

I tested the same slot, the PCIE4 slot, plugging in any of the cards directly, without risers, and it recognizes them normally.
I also tested the 3 16x slots together, plugging all of the cards directly in, without the risers, and all of 3 works fine.
I tested the other 2 16x slots of the MB with risers, and they recognize the cards normally.

So, why that single slot isn't recognizing the 1x-16x risers? Should I need to buy a 16x-16x for that slot? There's a way to fix it somehow?



And also, I've encountered another probem trying to avoid using that 16x slot, here the configurations I've tried so far:

Config A:
GPU 0 -> Riser plugged in PCIE 16x slot --> 700Kh/s
GPU 1 -> Riser plugged in PCIE 16x slot --> 700KH/s
GPU 2 -> Riser plugged in PCIE 1x slot --> 100KH/s

Config B:
GPU 2 -> Riser plugged in PCIE 1x slot --> 700KH/s
GPU 1 -> Riser plugged in PCIE 1x slot --> 700KH/s
GPU 0 -> Riser plugged in PCIE 16x slot --> 100KH/s

So, with both those configurations, all of the 3 cards are correctly recognized with the risers.
BUT, in both cases, the single card that has a different PCIE Interface compared to the other 2 cards (GPU 2 in config A & GPU 0 in config B) is having a really low hash rate for some reasons.

Why?
I think this could be a setup problem and I hope that you could help me fixing it.


Thank you in advance to anyone that will try to help me out.

Jsnow

Try uninstall AMD Catalyst and Reinstall with latest beta version - I think it is 13.11 something like that and Latest SDK(2.9?)

it solve my unstable issue..

Have you tried this?

http://blog.zorinaq.com/images/pcie-short-photo.jpg
http://blog.zorinaq.com/images/pcie-short-schematic.png

Obviously, some mobos need it to recognize that a slot is occupied (more info here: http://blog.zorinaq.com/?e=42)

By the way, I've got the same PSU as yourself. Are you sure that it is adequate for three R9 280x?

Cheers

Are they ribbon cable risers? Those don't have the presence short built in. The USB style ones like I sell do. To run the ribbon cable ones on some mobos you need that jumper.

I don't believe that the AX860 is a good choice for 3 x R9 280X, measured 1 x R9 280X (undervolted) with a current clamb, at full hashing the power was about 270W, that will be 810W in total, leaving 50W for everything else, you can properly squeeze 5-10% more of of the AX, but I would not recommend it, as the derating of the components will proberly lead to short life time of the PSU. I believe that the AX860 is a PSU you can have for many many years if you dont punish it too hard.