iMac 400 MHz G3 DV - DVD Firmware

"I'd really like to try out the AHT's of iMac versions 1.0, 1.0.1, 1.1, 1.2 and (iMac/eMac) 1.2.1... In the end I will probably realize that none of them will work on my device, but at least I tried."

Keep in mind that the first version of the AHT disk that shipped with the Summer 2000 iMacs wasn't backward-compatible with previous iMacs (including the 1999 models). Subsequent revisions were released to expand the AHT utility's database of supported newer models. You will experience the same result, no matter how early a disk you manage to find. Since you don't really need to run the test, it won't matter in the long run. I've never had a problem with my iMac DV, other than the nuisance, sluggish disk ejection that needs manual assistance.

I have a lime-colored G3 iMac DV (400 MHz) from 1999. The iMac DV SE that shipped in 2000 had a 500 MHz processor, a 30 GB hard drive, a 4x DVD-ROM drive, the marginally better ATI Rage128 Pro GPU, and 128 GBs of SDRAM. It was available in Graphite or Snow. The internal DVD-ROM drive may have had a sequentially newer model number, than that used in the 1999 models. I wouldn't be concerned about updating the firmware in your DVD-ROM drive - it is what it is - a 15 year-old computer with similarly dated hardware. I didn't receive an AHT disk with mine, and have had no reason to run it anyway. If you would like a much more modern internal DVD±RW drive, you can buy one here for $149. Obviously, that exceeds the value of your iMac. With onboard FireWire ports, I have used external CD-RW and DVD±RW drives, rather than replace the internal drive. A common problem with those slot-loading optical drives occurs when the neoprene sleeved rollers (that pull in and roll out the disk) get dry/slick with age. This will cause slipping and is usually indicated when the disk repeatedly gets stuck, as the motor keeps churning to eject it. I maxed out the memory at 1 GB and installed an 80 GB hard drive, but that's all. As for the resolution setting, I wouldn't be concerned about using a 60 Hz refresh rate (and dealing with the annoying flicker). Just select the optimal resolution & refresh setting. The greater concern for component failure in those iMacs is its Power-Analog-Video (P-A-V) board, which is the heart of the system's power. Replacement requires previous experience with CRT repair, because of the potentially dangerous stored electrical charge that must be properly discharged in order to swap P-A-V boards. Finding a new "old-stock" P-A-V board would be difficult, if not impossible today. Installing a used part with unknown remaining service life could be a waste of money. If you wish to boot from your Tiger installation, you can press/hold down the "X" key when you power ON the computer. That model also supports using the Startup Manager, which you can read about here.

"I was also told that there was a "iMac 400 MHz DV Special Edition" in mid 2000, which supported the AHT (1.0.1 (?)) and its only difference to my iMac 400 MHz DV would be the ATI 128 Pro instead of a 128 VR... So there might be still hope, if the AHT really came with some versions of the 400 MHz DV SE (2000)."

The iMac G3 400 MHz DV SE model was released in 1999, and although production continued until mid-July 2000, it's not considered a year-2000 product. For this reason, I don't think it shipped with the AHT disk. It was the same computer as the 400 MHz iMac DV "non-SE" 1999 model, because it had the same motherboard with the 400 MHz processor and Rage 128 VR GPU. The only specs that made it a "special edition" were the graphite color, having twice the amount of system memory, and a marginally-larger hard drive (13 GBs). The 500 MHz iMac DV "SE" was a 2000 release, having a faster CPU and better GPU (Rage 128 Pro) soldered to the motherboard. It also shipped with the Apple Pro keyboard and mouse. If you can't find that AHT disk with an earlier version, you can download version 1.2.2 for the summer 2000 and newer iMacs (here), but you'll need to burn a CD with the .img file under OS X. Unfortunately, you don't have a CD-R/RW drive. That's why I bought a Sony FireWire CD-RW drive many years ago and left it permanently connected to my iMac DV. If someone you know has an older Mac, ask him/her to burn a CD-R (Mac OS Standard or Extended format) for you. You'll probably receive an error message stating that it isn't compatible with your model iMac, but your curiosity won't be satisfied until you try.

"...people say I got a PowerMac2,1, others say I got a iMac...and not seeing G3 in that AHT enlisting confused me even more."

Your iMac falls within the broader category of a Power Mac - an Apple computer with a PowerPC processor.

"If it would only be a "incompatibility message" when booting the wrong AHT, I would have no problem with it, but others told me it MIGHT as well damage my iMac PowerPC2,1 G3."

When the AHT (v. 1.2.2) disk fails to boot your iMac (after checking the Machine I.D. and finding an unsupported model), you will receive the following error message: "Apple Hardware Test does not support this machine." There will be two options from which to select: Shut Down or Restart. You should restart, so that you can remove the AHT disk from the drive.

You may also want to look over the chart on this page, listing different Power Macs by model and the AHT version intended for them.