Problem installing Radeon 4870 in Mac Pro

[juanm]

Hi. I want to flash a 4870 to replace the aging and artifacting X1900XT in my Mac Pro 1,1.
I've got a Sapphire Radeon HD4870 1GB Part Number 288-20E85-130SA
I know some people have had success installing it, and I've tracked down the ROM they used.

I've also got the cables (both tested and working). And Zeus (BTW, thanks, Cindori, you'll soon get some $ more for your efforts). And the ROM.

The problem comes when I put my ATI X1900XT and my new HD4870 together in the Mac Pro (each with a power cable). A red LED comes up just behind the RAM cage, and although it's half hidden by the cage, it seems to read "CPU A" or "CPU B".

When I put the 4870 alone, in the slot 1, and only the windows-dedicated hard drive, instead of booting into Windows as I'd expect it to do, well, it just doesn't boot...

How can I flash the card?

 

[Cindori]

The 4870 requires two power cables.



To boot win from the 4870 you can not just keep the windows drive in, you have to boot OSX first and select Windows as startup disk. Then you can boot with onlythe 4870.


Some 4870's simply will not work to boot OSX with, even with a Mac card running the display. It will just kernel panic, hence the cpu LED
for those you will have to flash bootcd
bootcd guide is in my Golden Guide

 

[juanm]

This is what I get... with the X1900XT in Slot 1 and the HD 4870 in Slot 2, trying to boot in OS X:
The chime starts, but stops before it should

The red LED turns on.

As soon as I turn the Mac off, and take the 4870 out, everything starts working again.

 

[MacVidCards]

The 4870 requires two power cables.

Did you read this?

He isn't joking.

 

[juanm]

I know, I've also tried with two cables, and the same thing happens. I guess I'll flash it in a PC and try again later...

How is it that other cards allow booting into windows, and this one wouldn't even go through the startup chime before the red led would go up?

 

[juanm]

I just tried doing as Cindori said (setting Windows as startup disk), taking out the X1900XT and putting in the HD4870, and it still won't boot. I'll try it on a PC on monday...

 

[MacVidCards]

I just tried doing as Cindori said (setting Windows as startup disk), taking out the X1900XT and putting in the HD4870, and it still won't boot. I'll try it on a PC on monday...

Well, as you are having a problem that nobody else has reported in 1000s of posts, Im going to guess that something else is going on here.

You should try card in a PC and see if ti boots.

Might very well just be a buggered card.

 

[abccba]

This is what I get... with the X1900XT in Slot 1 and the HD 4870 in Slot 2, trying to boot in OS X:
The chime starts, but stops before it should

The red LED turns on.

As soon as I turn the Mac off, and take the 4870 out, everything starts working again.

I have the same card with the same problem.

The Card won't POST in a PC either....
I can flash it using ATIflash with a PCI video card, but it still won't POST in the PC.

I think it's dead... sorry mate...

 

[audio_inside]

The 4870 requires two power cables.

@juanm: How do you even get an x1900 and HD4870 powered simultaneously? There are only 2 micro Molex 12V connectors total on my MacPro1,1 mobo.

-Steve

 

[juanm]

I have the same card with the same problem.

The Card won't POST in a PC either....
I can flash it using ATIflash with a PCI video card, but it still won't POST in the PC.

I think it's dead... sorry mate...

Yep, it was dead... It's going back to the store. Oh well, it only means I'll have to wait more...

 

[paynito]

I have the same card sapphire hd4870

please keep us posted on your progress. I ordered the mac power cables and plugged the card in. I get a kernel panic "you need to restart, hold down the power key" I have not tried to use the card or flash it in a pc yet. how modern of a pc do I need to find to have one with power on the mobo for a heavy duty video card?