MP 1,1-5,1 Flashed GPU flickering

[vworks]

Hello,


I have a question about an issue I noticed with 2 GPUs.
I had a task to flash a 7950 or r9 280 card for a mac pro 5.1.
I have experience with this and flashed several ones already in the past.


But the first card r9 280 I was given showed a strange issue : kind of flickering, not often but like 1 or 2 times per 10-20 mins. I returned this card and took another one, 7950 dual X. After flashing and testing it, all works, bootscreen etc. BUT the same issue comes up, this time I recorded it.
I attach a screenshot from the video I made and the video itself. It does not look like artefact.

I dont know what to think. Is it related to the card itself? I used their own windows bios, for both of the cards, not overclocked (I checked), to create the macrom following the netkas script as always. If not the card, could this be related somehow to the mac pro (5,1)? I have my own card gtx 680 (flashed by me as well) inside usually and have never experienced these problems.


Thanks !
link for the video :

https://www.cjoint.com/doc/22_04/LDdkgHkJZOQ_IMG-5565.MOV

VIDEO

 

[amstel78]

Looks like a power related issue.

 

[vworks]

Looks like a power related issue.

Related to the card or to the mac pro?

 

[vworks]

@h9826790
Any ideas ?

 

[h9826790]

@h9826790
Any ideas ?

Should be HD7950 driver's issue. Apple never fix that.

If you are going to flash the card anyway, before you create the Mac EFI UGA ROM, you can mod the VBIOS by using VBE7 first. Just fix the VRAM at 1250MHz (or whatever reasonable number), the flickering should go away.

Screen Flickering with Sapphire 7950 Mac Edition

No question that you'll see a real improvement over a 5770. Couldn't scrape up the cash for an actual Mac Edition, so I'm running a flashed MSI Twin Frozr 7950 in my 4,1 that replaced the 4870. 10.9 has been a solid upgrade for performance. The little flickering I saw in 10.8.4/.5 are gone in...

forums.macrumors.com

 

[vworks]

Thanks a lot! Will do.