r9 290x

[yorich]

However, I undervolted GPU voltage by flashing GPU vBios on r9 280x and instead of 1.2V now runs on 1.075V and it's completly stable.

What software did you use to do that? And did you overclock core and memory clock?

+1...how the hell did you get a gigabyte r9 280x undervolted?   can you provide details?  I've tried to undervolt my cards but no such luck.   I'm pushing 940 watts from my 3 cards, hitting the wall of my 1000w psu.

[hakeriukasx]

Can i use different cards ?if yes .would i need install drivers of each card?

[thens]

What software did you use to do that? And did you overclock core and memory clock?

+1...how the hell did you get a gigabyte r9 280x undervolted?   can you provide details?  I've tried to undervolt my cards but no such luck.   I'm pushing 940 watts from my 3 cards, hitting the wall of my 1000w psu.

I've followed this guide. Step by step, everything worked fine:

http://rumorscity.com/2013/12/09/how-to-modify-video-bios-to-undervolt-gpu-in-linux/

Well my r9 280x is running on this setting. It just gives me best performance:

intensity : 13, thread-concurrency : 11200, gpu-threads : 2, gpu-engine : 1035, gpu-memclock : 1500, gpu-threads : 2

(I don't remember default parameters of GPU, so don't know if I should call it overclock )

[pontiacg5]

In my experience sapphire 280x's are faster than gigabytes by 20-30kh/s. I've had(have) over 10 sapphire 280x cards, had 6 gigabyte 280s and returned them before all the litecoin/scrypt craziness.

I only have one sapphire 290x, and it does 937kh/s easily. It did so on air reliably at 1025/1500, but under water it manages the same hashrate at 1002/1500. I don't experience any black screens or anything, but it is only one GPU.

[thens]

I wouldn't need to undervolt it, if it's electric bill you're talking about, but thanks for the replies  

It's not just about electric bill. It can also significantly lower temperature of GPUs.

[hakeriukasx]

http://www.amazon.co.uk/Sapphire-Graphics-Express-Display-Technology/dp/B00FZLFHEI/ref=sr_1_fkmr0_2?s=computers&ie=UTF8&qid=1388174790&sr=1-2-fkmr0&keywords=R9+290X%2C+100361SR#productDetails

I just bought one, guys if i mess my mining rig ill make good gaming pc  anayway what do you think about this card ,is good choice?

[pontiacg5]

http://www.amazon.co.uk/Sapphire-Graphics-Express-Display-Technology/dp/B00FZLFHEI/ref=sr_1_fkmr0_2?s=computers&ie=UTF8&qid=1388174790&sr=1-2-fkmr0&keywords=R9+290X%2C+100361SR#productDetails

I just bought one, guys if i mess my mining rig ill make good gaming pc  anayway what do you think about this card ,is good choice?

It's a very good card, and if you follow my directions with a good TC (1025/1500) you should get around 900kh/s.

[hakeriukasx]

Thank you next step i got motherboard this one http://www.gigabyte.com/products/product-page.aspx?pid=3891#ov waiting your opinions.