So, Apple invented the iMac. It was a step back in time... to a certain extent. Rather like re-inventing the wheel, they took a step back and put the entire computer in a single case. Just like the 5000 series of powermacs and the G3 (all in one) which was only available in the States, the case housed the computer and screen. The main difference, other than the colour, was the chassis which housed the computer itself. Previous all-in-one Macs had housed the screen and computer with the motherboard being a slot loading unit. This time, they changed the rules. The computer itself was housed in it's own steel casing which slotted in underneath the screen. Cables connected the computer to the power supply, built in stereo speakers and screen, allowing pretty simple removal and upgrading of memory and hard drive. Costs were considerably less than Apple's high end Powermac range, aiming the iMac at the average consumer market rather than specialist IT users.
Original iMac Specs:
memory: 32 megs upgradable to 256megs
Hard drive: 4 gig apple stock
CD rom drive: 24 speed
Video: 2 megs vram to board. 4 meg upgrade option available
Screen: 15 inch standard CRT
Ports: 2 x USB ports, Stereo sound out, sound in
Processor: G3 running at 233mHz
The downside to the original iMac was upgradability. Although the Processor was on a daughtercard, it wasn't as easy to upgrade to a faster processor as the G3 desktop and mini tower. Memory was different as well. Gone were the standard 168 pin dimms, replaced with 144pin memory sticks. The original series of iMac came with 2 slots to the daughter card, allowing it to address up to 256 megs of ram.
The G3 iMac had a great design that allowed the upgrading of the hard drive. By removing the cd rom drive, the existing apple stock 4 gig hard drive coule be removed and replaced with a unit up to 128 gigs. Unfortunately, the rom can't address a drive larger than that and besides, with the original iMac being limited to OS 10.2 at the most, there isn't really any point in being able to add a larger drive.
The original iMac was limited to Bondi Blue. This being the first generation was soon changed with the advent of the iMac 266mHz. With a speed bump, came the advent of the Tangerine iMac. The design was exactly the same from the exterior, but under the hood, the 266mHz iMac incorporated a faster processor and the removal of the 8 pin mini din port running from the logic board to the guts of the unit. Unfortunately, this means that you can't remove the computer from the 266 and put it in the casing of a 233. Saying that, the processor from a 266 with of course run on a 233 motherboard.
iMac 266mHz Specs:
memory: 32 megs upgradable to 256megs
Hard drive: 4 gig apple stock
CD rom drive: 24 speed
Video: 2 megs vram to board. 4 meg upgrade option available
Screen: 15 inch standard CRT
Ports: 2 x USB ports, Stereo sound out, sound in
Processor: G3 running at 266mHz
The stakes were upped a little further with the release of the 333mHz iMac. The speed bump improved performance significantly and the mac was made more productive through the addition of a 6 gig ide hard drive. Strange though that Apple matched units containing a G3 processor faster than 300mHz with a 6 gig hard drive they did exactly the same thing with the Beige G3 desktop and mini tower and the blue and white G3 300mHz came with a 6.4 gig Apple Stcok unit.
iMac 333mHz Specs:
memory: 32 megs upgradable to 256megs
Hard drive: 6 gig apple stock
CD rom drive: 24 speed
Video: 2 megs vram to board. 4 meg upgrade option available
Screen: 15 inch standard CRT
Ports: 2 x USB ports, Stereo sound out, sound in
Processor: G3 running at 333mHz
The biggest problem with the original range of iMacs was the pram battery. Experience has taught us a valuable lesson with these units. Over the age of 3 years, we've found that the original iMac series would inexplicably die, for no reason whatsoever. Swapping out the pram battery and resetting the computer by holding down the cdu-c switch for 30 seconds usually brings them back to life.
Of course, the original iMac caddy loader was eventually replaced, as is always the case with any Computer. The iMac 350mHz was a significant change, although ultimately the case design retained the same popular look. The biggest visible chhange was the removal of the cover to the ports bay. Instead, Apple opted to leave these visible. A great option considering the fact that the USB cabling was covered in a clear plastic resin, which allowed the wires to be visible. The most obvious mechanical change was the removal of the drawer loading cd rom drive. Rather than pressing a button on the front of the iMac , only to have a drawer spat out of the casing for CD roms, the new iMac sported a slot loading cd rom drive, which sucked users cd roms into the mac. To eject the cd, users just had to drag it to the waste basket and it was spat out again.
Under the hood, the iMac had changed completely. The computer was no longer retained in it s own metal chassis. Instead, the motherboard was bolted to the underside of the cage around the screen itself. Cooling of the processor was via a heat sink on the steel cage and the iMac motherboard was a single unit so the processor could no longer be upgraded. A flyback unit to the side of the motherboard took voltage from the board itself regulated it for the screen. 2 groups of connectors connected power and video signal between the motherboard, power supply and the screen.
The major difference between the iMac 333 and the 350 model was the increase in bus speed on the motherboard which went from 66mHz to 100mHz. Memory changed from the 144pin dimms to 168 pin dimms, adding flexibility via 2 x slots. Accessibility to the memory slots was via a port on the underside of the iMac, which proved far more easy and popular for users looking to upgrade their iMacs. The casing also took on a clear rather than smoky look, adding to the appeal of the iMac by allowing users to see the electronics inside the iMac.
The hard drive remained the same in this model of iMac, which as with the 333 was set at an Apple Stock 6.4 gig unit, but this didn't seem to affect the performance of the computer, which compared to the tray loading unit was considerably faster.
The iMac 400, which was also released as the 400DV took on a rather more serious edge over it's predecessors. Whilst retaining all the previous changes, it also added a video port to the rear of the unit, allowing for the addition of a seperate external monitor. The processor speed increased 50mHz to 400mHz and with the DV came the use of a DVDrom slot loading unit. The greatest addition was the twin fireiwre ports, which added FW400 capability and an edge not available with previous models. |
