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interesting, altho I thought the mac cards had more rom for the macintosh boot code?

 

will be interesting to know if this flashed card is being used as a secondary card or primary as I've heard of people using pc cards already on their mac pro's in the secondary slot.

The way it reads, it looks as if there is an EFI bit and a bios section of the rom. Apple originally went to larger rom chips to prevent pc cross flashes not out of necessity. It also looks like the card works as the primary one without the need for a second "boot" card.

I found this information a while ago:

'PC' video card ROMs are only 64K, whereas 'Mac' cards are 128k. The reason for this is so that Apple can have full-color and full-resolution boot sequences and boot menu (what you see when you hold down option).

Therefore, whatever ends up happening, all PC video cards on a mac (if they run at all) will have a black screen until the OS loads the driver. This hand-off between the video card's ROM driver and the OS driver occurs just before the login screen. (2)

If this is true then it would be physically impossible to flash a 64k card with a 128k bios :help:

 

Altho the BIOS given on that forum seem to be 64k which is strange :)

 

Also the way it is explained is that the ROM was taken from booting from a pc (BIOS driven) which might explain why it is only 64k and not the full 128k. Which would in theory mean the 64k that contains the apple boot menu would not be included?.

 

Which is why I was wandering if it was used as a primary card :(

It could work without the boot menu tho.

 

Bah :) guess we will see in time if this is true or not. :D

I found this information a while ago:

'PC' video card ROMs are only 64K, whereas 'Mac' cards are 128k. The reason for this is so that Apple can have full-color and full-resolution boot sequences and boot menu (what you see when you hold down option).

Therefore, whatever ends up happening, all PC video cards on a mac (if they run at all) will have a black screen until the OS loads the driver. This hand-off between the video card's ROM driver and the OS driver occurs just before the login screen. (2)

If this is true then it would be physically impossible to flash a 64k card with a 128k bios :blink:

 

Altho the BIOS given on that forum seem to be 64k which is strange :)

 

Also the way it is explained is that the ROM was taken from booting from a pc (BIOS driven) which might explain why it is only 64k and not the full 128k. Which would in theory mean the 64k that contains the apple boot menu would not be included?.

 

Which is why I was wandering if it was used as a primary card :(

It could work without the boot menu tho.

 

Bah :) guess we will see in time if this is true or not. :)

 

 

Odd, when I used a reduced 64k (that had the boot drivers removed) rom on a 9800p I still got the option boot menu... those things are a bit like your appendix, not very useful but can cause problems and not missed if removed. The only thing that did NOT work is the mollex unplugged warning i.e. if you turned on the computer w/out the mollex plugged in it would just hang instead of giving you the little "plug the damn cable in you idiot" graphic.

 

It takes 15 minutes to swap a rom chip from 64k to 128k ;)

 

Files size is not always directly related to bios size, the 64k reduced 9800 rom is 24k for example, some are compressed.

Odd, when I used a reduced 64k (that had the boot drivers removed) rom on a 9800p I still got the option boot menu... those things are a bit like your appendix, not very useful but can cause problems and not missed if removed. The only thing that did NOT work is the mollex unplugged warning i.e. if you turned on the computer w/out the mollex plugged in it would just hang instead of giving you the little "plug the damn cable in you idiot" graphic.

 

It takes 15 minutes to swap a rom chip from 64k to 128k :)

 

Files size is not always directly related to bios size, the 64k reduced 9800 rom is 24k for example.

ic :blink:

 

Might take longer than 5minutes to replace a soldered rom chip and be a lot of hassle. But that forum says nothing about replacing the rom.

 

I guess the 128k rom might only have 64k used, but then why do apple use 128k roms instead on 64k ones? :(

 

It does sound too good to be true as someone said in that thread. But I guess we will see.

1st off it is in fact a 64k rom. The Apple ATI card only has an EFI firmware on it whereas the nvidia card may be a hybird (hence the size difference). The old Mac firmware was 128k, but this was due to startup resolutions for open firmware. Bootcamp installs a bios compatability layer for the mac EFI. This is why the Radeon works in windows, but will probably not work in a standard x86 machine. Presumably when EFI is adopted by the whole industry there will no longer be a difference between a mac and a standard PC video bios.

news about this,

 

from what i have read...

the latest boot camp can make those cards to work magically under windows... (the flashed ones) so.. what the hell is boot camp doing?

 

Nothing magical here... all PC cards work in Mac Pro just not under OSX but under win... no bootcamp required...

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