ATI Radeon 9800XT repair and flash

Discussion in 'PowerPC Macs' started by harrymatic, Mar 26, 2014.

  1. harrymatic macrumors 6502

    Joined:
    Dec 30, 2013
    Location:
    United Kingdom
    #1
    Just thought I'd post what I've been up to lately in my ongoing saga for a souped-up MDD G4. I was given a broken ATI Radeon 9800XT 256MB - I tested it in my rubbish old Windows box and sure enough, it displayed the classic symptoms - corrupted text mode graphics and artifacts in standard screen modes. Anything 3D would simply crash. This nearly always means that a connection going to one of the video RAM ICs has been broken.

    Interestingly, one of the electrolytic capacitors had gone bad and leaked electrolyte over part of the board. I cleaned this up with isopropyl alcohol and desoldered the bad cap. Whether or not this was related to the main problem I'm not sure, but it needed replacing either way.

    I then baked the card in the oven for 10 mins at 200C to reflow the dodgy solder joint(s) under the GPU core, let it cool back down and reassembled it with new Arctic Silver 5 compound (re-did my CPU as well while I was at it). I soldered on a new 470uF cap in place of the old one. I just used a regular through-hole part instead of surface-mount.

    The card worked great after the repair. I left it running the Halo timedemo on a loop for an hour and it was all good. I was surprised at how cool that card actually ran, especially as I've heard people saying it runs extremely hot.

    Next on the agenda will be to flash it with the Mac firmware. I'll probably be doing this tomorrow so stay tuned :)
     

    Attached Files:

  2. eyoungren macrumors P6

    eyoungren

    Joined:
    Aug 31, 2011
    Location:
    Phoenix • 85037
    #2
    Let us know how that goes. I've got an NVDIA 5200 FX I'm working on and if your process to flash is as simple as it was for the SATA card I'd like to see it and then adapt the process for mine.
     
  3. Intell macrumors P6

    Intell

    Joined:
    Jan 24, 2010
    Location:
    Inside
    #3
    The flash process for ATI and Nvida cards isn't very compatible. In general, Nvidia cards are easier to flash.
     
  4. harrymatic thread starter macrumors 6502

    Joined:
    Dec 30, 2013
    Location:
    United Kingdom
    #4
    I was actually planning on flashing the card from within OS X, as unlike the NVidia OS X flash utility, the ATI program is able to write firmware to cards that do not already have valid Mac firmware - i.e. the PC ROM.

    I understand that it only works reliably under Tiger, but that's fine as I have an old 20 gig IDE drive with Tiger installed and working.
     
  5. harrymatic thread starter macrumors 6502

    Joined:
    Dec 30, 2013
    Location:
    United Kingdom
    #6
    Part 2...

    OK, I've had a bit of time to play around with flashing the Mac firmware. I found two potential ROMs that I could use, the 256MB Pro ROM and the XT ROM (both of which are from http://www.themacelite.wikidot.com/flasher-s-buying-guide-9800). The Pro ROM supposedly allows for the DVI port to output digital video, and runs slightly faster than the XT ROM. When I tried booting with it, I just got a corrupted mess - you couldn't really see anything on screen.

    I then tried the XT ROM. With this ROM, the DVI port only outputs VGA (via an adapter). It seemed fine at first, but after a while the screen started to get the artifacts which I thought I had fixed previously. On a hunch, I reduced the core and memory clock speeds using Thomas Perrier's excellent ATIcellerator utility, both by 10%. All graphical artifacts vanished completely. Despite the fact that it was running underclocked, the card performed amazingly well - all of my games ran incredibly smooth, even Doom 3 never dipped below 30FPS - with the settings on max! :D

    I suspect the reason why the Pro ROM didn't work was because the core and memory were clocked too high. I'll have a go at making a custom Pro ROM, with reduced clock speeds hard coded in the firmware - I'll try this tomorrow. I've been using Graphicelleator to flash the firmware, with an old ATI Rage 128 to see what I'm doing. It turns out that OS X Leopard is fine for flashing the firmware - no problems whatsoever.
     

    Attached Files:

  6. harrymatic thread starter macrumors 6502

    Joined:
    Dec 30, 2013
    Location:
    United Kingdom
    #7
    Part 3...

    And here's the conclusion. I found a post in this forum from a few years back where the OP had the exact same problem: http://forums.macrumors.com/showthread.php?t=634519

    It links to another 9800 Pro ROM that does work. I didn't have to tweak any clock settings at all, it works perfectly. I've been running the card for a few hours now and nothing's gone wrong so far, so hopefully all is OK.

    As it is the Pro ROM instead of the XT, the DVI port is fully operational. This also means that all of the extra functions provided by the ATI Displays utility are enabled. Dual monitors worked fine.

    The fan on this card is very loud though, so I might look into getting an aftermarket cooler for it. All in all, I'm very happy, especially as I got the card for free! I'm more or less at the end of this Mac upgrade journey now (apart from maybe an SSD and/or a larger hard drive), and I've had a blast. This Power Mac G4 runs so well now, I'd be happy using it as my main machine.

    For anybody interested, I've attached the good ROM file that I ended up using.
     

    Attached Files:

  7. mark8 macrumors member

    mark8

    Joined:
    Nov 29, 2010
    Location:
    WNY
    #8
    cool. I did surgery soldered(larger 128k rom, then flashed it in a pc) on an Ati 9800XT a few years back, following the macelite site. You are correct on the fans they are loud(had to replace, it stopped working).
    Did it before I found Graphicelleator
    thx for the info may have to try different rom
     
  8. harrymatic thread starter macrumors 6502

    Joined:
    Dec 30, 2013
    Location:
    United Kingdom
    #9
    By the time I got into Mac card flashing, people had already managed to put together reduced 64K roms - much to my relief, as I'm not sure I could face swapping the EEPROM. :rolleyes:

    I have noticed that occasionally the computer just starts up with artifacting all over the screen - but this always goes away again on a restart. Sometimes it happens when resuming from sleep mode as well. I'm not too fussed though, this card was free and the rest of the time it performs brilliantly.
     
  9. mark8 macrumors member

    mark8

    Joined:
    Nov 29, 2010
    Location:
    WNY
    #10
    Can't go wrong when it's free. The artifacts may/not have to do with the reduced rom. Some cards had the larger eeprom on board(can look it up online), which really is not to hard to swap(desolder/solder in new one) problem is have to buy more than one, when you order
     

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