mac with pc graphics card problems

[damn123]

hello every one i'm in need of some help with my friends mac she got a new AMD graphics card for her mac she is running 10.7.5 she has flashed the card to work for mac and it was working fine for a while but now its showing signs of artifacting and its not showing full use of the card i tryed it on my pc and the card runs fine any ideas would be much helpful thanks.

 

[howiest]

Which card, and which Mac Pro?

If it's a Radeon R9, she will need to install new drivers because her OS is older than 10.8.3.

 

[damn123]

Which card, and which Mac Pro?

If it's a Radeon R9, she will need to install new drivers because her OS is older than 10.8.3.

It's a Radeon 5770 and its a mac pro 1,1 2007and thanks for help

 

[cw48494]

Try to push the clock speeds down a little bit and see if the problem persists.

 

[damn123]

Try to push the clock speeds down a little bit and see if the problem persists.

thanks ill give it a shot ...tho she is not getting full clock speeds as it is here is what it shows in the attachment thanks for any help