Screen flickering - Mac Pro 1,1 with El Capitan and 7300 GT

MortenMoulder

macrumors member
Original poster
Feb 20, 2017
34
2
Today I finally got El Capitan working on my Mac Pro 1,1. However, everything is flickering and I can't figure out why. When I load up system information, it says 8MB VRAM instead of the 256MB VRAM it normally has.

I would normally install a driver on Windows, but on OS X I'm kind of new to this "3rd party" stuff. I know kexts and so on, but I have no idea if finding the right one would work or anything like that.

Anyone know what's up? It looks like it's only hardware accelerated apps, but same issue even if I turn hardware acceleration off.

Any help is highly appreciated! Thanks.
 

jbarley

macrumors 68040
Jul 1, 2006
3,769
1,614
Vancouver Island
Today I finally got El Capitan working on my Mac Pro 1,1. However, everything is flickering and I can't figure out why. When I load up system information, it says 8MB VRAM instead of the 256MB VRAM it normally has.

I would normally install a driver on Windows, but on OS X I'm kind of new to this "3rd party" stuff. I know kexts and so on, but I have no idea if finding the right one would work or anything like that.

Anyone know what's up? It looks like it's only hardware accelerated apps, but same issue even if I turn hardware acceleration off.

Any help is highly appreciated! Thanks.
A common and well documented issue..

Here is a short quote from this Link

"The 64-bit EFI loader is not optimized to work with graphics cards smaller than 512 MB. The catch-22 here is that if you run a larger PC card, you will not see the verbose screen upon start up. The card will not initialize until OSX’s GUI loads, so your Mac Pro will not send signal to the monitor until fully booted. Conversely, if you stick with the Geforce 7300GT or one of the other earlier GPUs under 512 MB designed for variants of the Mac Pro, OS X will read it as a 5 MB or 7 MB graphics card instead of the 256 MB that it is. Ideally, you’ll want to have a Mac compatible card that is at least 512 MB during upgrades such as the Geforce 8800 GT."
 

MortenMoulder

macrumors member
Original poster
Feb 20, 2017
34
2
A common and well documented issue..

Here is a short quote from this Link

"The 64-bit EFI loader is not optimized to work with graphics cards smaller than 512 MB. The catch-22 here is that if you run a larger PC card, you will not see the verbose screen upon start up. The card will not initialize until OSX’s GUI loads, so your Mac Pro will not send signal to the monitor until fully booted. Conversely, if you stick with the Geforce 7300GT or one of the other earlier GPUs under 512 MB designed for variants of the Mac Pro, OS X will read it as a 5 MB or 7 MB graphics card instead of the 256 MB that it is. Ideally, you’ll want to have a Mac compatible card that is at least 512 MB during upgrades such as the Geforce 8800 GT."
Ah damn, that sucks! So I'm forced to go out and buy/aquire a better GPU? That sucks :( Oh well, I might have some old AMD 5450 laying around or something. I know I have a GTS 450, but whether it works is unknown.
 

fhenry

macrumors regular
Feb 28, 2012
114
0
Ah damn, that sucks! So I'm forced to go out and buy/aquire a better GPU? That sucks :( Oh well, I might have some old AMD 5450 laying around or something. I know I have a GTS 450, but whether it works is unknown.
The gts 450 will work
 

satishm_us

macrumors newbie
Nov 17, 2018
2
0
India
Today I finally got El Capitan working on my Mac Pro 1,1. However, everything is flickering and I can't figure out why. When I load up system information, it says 8MB VRAM instead of the 256MB VRAM it normally has.

I would normally install a driver on Windows, but on OS X I'm kind of new to this "3rd party" stuff. I know kexts and so on, but I have no idea if finding the right one would work or anything like that.

Anyone know what's up? It looks like it's only hardware accelerated apps, but same issue even if I turn hardware acceleration off.

Any help is highly appreciated! Thanks.
I have the same issue running el capitan in mac Pro 2,1 with 7300gt GPU.....but when i install another GPU GT 610 it works fine.