Radeon 7500 PCI PC to Mac Flashing

[quadra700]

Hello everyone, a couple questions.

First, I have a Radeon 7500 PCI that I would really like to get working on a PowerMac G3 to be used with os9 and os x. Looking at the Mac Elite downloads, I see a rom for the AGP version of this card but none for the PCI version. Can I flash this rom or will there be issues? Guessing a rom from the 7000 or 7200 would not work? Did a lot of searching for info on this card but there really isnt much out there, doesn't seem like people have used this card in a powermac on PCI.

Second, I also just got a Radeon 7000 that I intend to flash for use in another G3. This one is a sapphire card and while the reduced ROM should work just fine, I am wondering how to flash the card if I replace the rom chip. Do I need to program the rom with a rom programmer? Or could I just solder on the new chip and flash the card that way?

Lastly, I have a Radeon 9250 PCI that I would also like to flash for use in macs. I didn't reall have high hope for this one but I saw a recent post about this card from another memeber and now I'm thinking it would be nice to get this one working as well. There is a rom available for this card on the TME wiki as well, under the "Modifed ATI PPC Macs" category, is this the one I should be using?

Any and all input is appreciated. Yes, I really do have 3+ g3's for these cards to all go into so while it would be nice to get them all flashed for macs, I would consider just one or two a win. Thanks!

 

[Byrd]

Hi,

The Radeon 7500 is quite a different card from a Radeon 7000, it also has a different IGP RV100 vs RV200. In short, you will likely have difficulty finding a working Mac BIOS for the card.

The Sapphire Radeon 7000 should flash over easily, you will need to identify the ROM chip and part number to see if it comes with a 64KB or 128 ROM. The flashing is most frequently done using a DOS based PC, you can desolder and flash the ROM in a programmer however this the former method is much easier.

The Radeon 9250 is similar to the Radeon 7500 in being less commonly flashed over, and Radeon 9250 cards were usually ultra budget GPUs (unlike the Radeon 7500 which was more a high performance card when released). Yes, if your card looks close to a reference design and the Mac BIOS matches up with similar RAM speeds to your card, I'd give it a shot. You also need to relocate some resistors on the card.

If the 7500, 9250 fail you can flash back the BIOS make sure you save the old one! If all else fails, I'd find some more cheap Radeon 7000 cards for your G3s.

9250 Trick - The Mac Elite

themacelite.wikidot.com

JB

 

[quadra700]

In a turn of events, I am not going to be able to flash the Sapphire since its ROM chip is a model that doesnt play nicely with graphicaccelerator. I did order replacement, 128k ROM chips but they are coming from China and will likely take some time to arrive.

On the other hand, I was able to successfully flash the 7500 PCI with the rom on TME and got no errors. However, while the mac does boot with the card, I get garbage on the display. Could this be a driver issue or was the rom just not a good match for the card? Unfortunately, I did a dummy move and did not test the card in a pc before flashing to confirm it worked.

I'm still not clear on flashing the new ROM chips, do I need a programmer for them or can I just solder the blank ROM chips onto the card and flash that way?

 

[Byrd]

If the flash was successful, it should work from boot. As mentioned flashing a generic PCI 7500 using the Apple AGP 7500 probably won't work, and core/mem speeds are probably also not lining up.

With the new ROM chips you will need to remove old, then resolder new and run off a donor PCI x86 box using DOS. You'll also need a working PCI video card to see what you're going with the R7000 also plugged in.

What's the incorrect ROM with the Sapphire card? There are reduced 64K ROMs for the card.

JB

 

[quadra700]

Well, things weren't going too well with the 7500, even after adjusting the core and memory frequencies.
Since I was starting to get a little anxious and just wanted to get something working, I had the idea to swap over the rom chip from the 7500 to the sapphire.
Why? Because according to TME, the model of the chip on that 7500 should be a 128k rom, and indeed I had been flashing with 128k rom files successfully. Not only that, TME said this chip works well with graphics accelerator and the ati flash program on mac os, which again, is what I had been using to flash the 7500.
The rom chip on the sapphire is one that TME says doesnt work too well with the mac ati flasher, and also this is a 64k chip so I wanted to replace it with a 128k chip anyway. And I'm glad I did because it worked. Desoldered the rom chip from the 7500, soldered it onto the sapphire 7000, stuck the card in my PowerMac Quicksilver, flashed it, rebooted and it worked!
Here it is in one of the G3's running mac os 8.6 driving two studio displays-