ASUS EAH5850 crossfire setup question

[jynks]

Hi all,

I am planning to buy a second ASUS EAH5850 graphics card to run in crossfire but the newer version card (TOP model) has a stock clock speed of 4500Mhz and ram speed of 1125Mhz while my current card has a clock speed of 4000Mhz and ram speed of 1000Mhz. I have never used crossfire before but i have heard conflicting explanation of how to set it up and i was wondering which was correct.

I have been told that to run them in crossfire i will have to manually match the speeds and voltages, and i have also been told that once i put the crossfire jumper across them the faster card will automatically throttle down to match the slower card. Which is true?

Also as I have never done this before if you guys could offer any advice as to how to make the process smooth and trouble free it would be greatly appreciated.

System specs are as follows:

ASUS P6T Motherboard
ASUS EAH5850 Graphics Card
intel core i7 CPU 920 @ 2.67Ghz
6 gig triple channel Corsair 1333Mhz 9-9-9-24 ram
Windows 7 64bit

Thanks very much,

Jynks

 

[jynks]

Hi thanks very much for the reply!

I looked into overclocking the first card and read a few forums about it but i didn't find anyone who had OCd it to 4500/1125 which is what i need to match up with the new card, best i could find was 4600/1025 so I am not sure if my current card will handle the match up especially the ram speed to the new card, also I have never OCd a graphics card before so i dont want to burn it out and / or break my mother board by tweaking the ram or voltage too high.

As for running them both at their differing stock speeds in crossfire I have been told that crossfire requires that both cards be running at identical voltages, gpu speeds and ram speeds, is that not the case??

Thanks for the reply!

sorry i just read your post again and realized you said it would match the slower speed! Apologies and thanks for the info!

Can you offer any tips on overclocking my old card to match the new one?

Thanks!

 

[jynks]

Current Card:

http://www.asus.com.au/product.aspx?P_ID=rnDoHsWYbCfL2EnH&content=specifications

New Card:

http://www.asus.com.au/product.aspx?P_ID=6Kz9jp2PUnDKZf67&content=specifications

i think the new card has a faster speed cause of the cool heatsink?

Thanks again!!

 

[jynks]

Ok wow.... I thought my current card had a gpu speed of 4000Mhz and a ram speed of 1000Mhz and that both those speeds needed to be brought up to match.

so the gpu runs at 725 mhz? When increasing this speed to 765 and pushing my memory clock to 1125 what voltage should i be using? I dont want to fry my car :s I have read you just need to slowly increase all of them bit by bit and hope your system remains stable but yeah i dont want to go too high and break it.

Also what is a good program to control the speeds and voltages with? Is ASUS smart doctor the best way to go?

Thanks so much for you help and quick replies!!

 

[jynks]

Ha amazing you have been so helpful! So if I use Ati overdrive to push the speeds up then connect the new card with the crossfire link they will run at the new cards speeds?

Would extra cooling be required for the old card I should I just push the fan speed up? Also what max temp should I be running at not to hurt the old card?

Thanks again!!

 

[jynks]

Ah ok thanks man you have been so helpful. I have been getting heaps of conflicting advice from different computer stores and forums but you have really simplified it for me!

I will download overdrive and have a crack at this, if i have any trouble i will let you know

Thanks again so much you are awesome

 

[jynks]

Best answer selected by jynks.

 

[Mousemonkey]

This topic has been closed by Mousemonkey