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l008com · 07:17 AM

So I have an 8500 with 256 MB of RAM. Its hard drive has a fresh install of 9.1 on it. Now with a 133 MHz 604 (not its original, but I had it kicking around) it boots up into OS 9 over and over again no problem. But when I try to stick the G4 in there, it comes on and flash with a [ ? ] floppy as if it can't find the startup disk. The G4 is a 450 Mhz G4 zif in a Zif carrier. Everything is supported, it all should work, it jut strangely doesn't. I really can't figure out any reasons why it wouldn't boot. Any help would be appreciated.

Lateralus · Jan 25, 2004, 08:22 PM

I had a similar problem with an 8600 of mine. If I recall correctly, I unhooked the motherboard from the power supply and removed the battery, left it like that for a few minutes. Then hooked it all back up and zapped the crap out of the PRAM. I think that did the trick.

Good luck.

l008com · Jan 25, 2004, 08:43 PM

No Luck. I just revived my old 9500 clone that I thought had a bad motherboard. Turns out it must have been this processor all the time. Same exact deal with it, it will boot with a 604 but with the G4, ? .. ? .. ? .. ?
The only adjustments you can make on the processor card are for speed. So I don't know I guess I have a bad processor card. ALthough, I don't know if its the card, or the processor itself. Damnit.

l008com · Jan 30, 2004, 05:58 AM

No one else has any ideas?

voyageur · Jan 30, 2004, 08:07 AM

I had a problem like this when I tried to upgrade my 8500 to a G4 some years ago. I spent about a month on it, tried everything, even finally brought to an Apple technician, and nothing could get it to work with the upgrade, although Sonnet assured me it should work. I finally returned the processer and bought a new G4. So good luck!

l008com · Jan 30, 2004, 08:09 AM

I think I'm on to something, these XLR8 cards require a 'virtual firmware' update to run G4 procs. As far as I can tell the only way to get this update is for you to run the daystar speed control software, which is NOT free. So basically I need to pay for this processor AGAIN to use a G4 in it. I'm still looking in to it to see if I have other options.

voyageur · Jan 30, 2004, 08:15 AM

I also have some vague memory about having to remove the L1 or L2 cache before using the upgraded processor...can't remember exactly anymore.

l008com · Jan 30, 2004, 08:23 AM

Yeah but I think now most upgrade software can automatically disable it, and i don't think that prevented a boot, but rather just lagged the processor a bit.

l008com · 05:40 AM

OK the Virtual Firmware thingie did work. And you don't have to buy that speed control thing to get it either. So I got my CPU to boot right up after that. It was a 450 MHz G4 and the PowerTower's max bus speed is 50 MHz, but for some reason, when this carrier card booted in non-OS X, the speed would get increased, so to start I set the speed low. I added components slowly, one at a time. And the machine was running great booted in 9.1 running off a SCSI hard drive, with two IDE drives connected to its IDE card, and using a Radeon 7000 for video. The radeon even worked fine when I booted from a floppy (for the firmware). So everything was working great, so I grabbed XPostFacto and installed 10.3. It was slow, but it also worked great. 10.3 worked no problem. I restarted, shutdown, shutdown and let it sit, over and over a bunch of times, just to make sure it would continue to boot up, and it did every time. So 10.3 worked but it was slow as nuts, as the processor was only running at 366 MHz and the system bus was only 40.666 MHz, so I shutdown, and turned the dip switches to 50/450MHz. remember the switches are accurate when you boot OS X, they only speed up in OS 9, strangely enough. So I put the processor back in and rebooted, and I got nothing. No video, no HD activity. The volume is messed up anyway so I really don't know if these was a startup chime or not. So first thing I tried was turning the speeds back down, first to where they were, then to as slow as I could get them, which i believe is 40.6Mhz bus and only a 4X multiplier Still nothing. I reset the CUDA a crap load of times, again, nothing. I even tried booting from a floppy. Everything powers on, but there's just no activity, no HD noise, no video. Its very frustrating!! I can't figure this machine out for the life of me! Also, back in the beginning when everything worked, i got a firmware updater for my ATA card, turns out it was already up to date, but I "freshened" it up anyway. I haven't had this machine working right ever since I swapped it's CPU from a G3 to a G4. Everything I have is supposed to work no problem with a G4, especially one thats merely a 450 MHz! I'm very open to any ideas here, I'd love to replace this machine with a Blue and White G3, but I just don't have the money, so I'm stuck with this crapbox.