iMac G3/266 Processor Upgrade And Discussion Page - Performance Of Latest G3 Processor Upgrades


The iMac was the first complete machine that was the result of the "2nd Coming of Jobs" era. Its unique all-in-one futuristic design, speedy processor, low price and excellent marketing propelled it to become one of the best selling computers of its time. The revision C version of the iMac was released at the January 1999 Macworld in San Francisco, a short 6 months after the initial release of the original iMac. As of the release of version C, Apple had sold over 800,000 units of previous iMac versions. According to Apple 40% of purchasers were first time computer purchasers and Wintel converts.

The revision C iMac has a few modest technological improvements over the previous revision. There is a small processor performance boost (from 233Mhz to 266Mhz), a larger hard drive (6GB instead of 4) and the machine came with OS 8.5.1 installed which fixed some bugs in the original release of 8.5. The biggest change with revision C was in its looks. The iMac came in 5 Lifesaver colors; strawberry, lime, tangerine, grape and blueberry. In addition Apple dropped the price on the revision C iMacs 8% from the price for the previous version. 

Apple showed, with the iMac, that it had really got on the ball again in marketing and generating interest in its products. The changes to the C version are really rather modest in terms of technology, but when combined with the cosmetic changes, the C versions made quite a big splash. Apple's efforts showed just the type of care and nurturing of its product line that had been woefully missing in previous years.

The machine sports a G3/266 processor with 512K of backside cache running at 133MHZ. It came with an anemic 32MB of Ram installed, which could be expanded to 128MB at the time of its release (see "Facts At A Glance"). The CD-ROM drive is 24X and is rather noisy in operation. It is the same CD drive found in the PowerBooks of the time, and does not have a powered drawer. It is kind of fragile for school use.

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iMac G3/266
  • Processor: G3, 266 MHz
  • Backside Cache: 512K, 133MHz
  • Data Path: 64-bit, 66MHz
  • Drive: 6GB ATA
  • Installed RAM: 32MB
  • Max RAM: 512MB
  • RAM Slots: 2, 144-pin SO-DIMM
  • Min RAM Speed: 100MHz/10ns
  • Graphics: ATI Rage Pro Turbo graphics controller
  • VRAM: 6MB (Max 6MB SGRAM)
  • Introduced: 1/99
  • Discontinued: 4/99
  • Initial Retail Price: $1,199
  • Current Price
    Special Notes
  • Included 56K internal modem
  • 4 USB ports (2 on keyboard)
  • Built-in 15" monitor
  • Built-in 10/100 Ethernet
  • Mac OS Supported: 8.5.1 - 9.x

iMac & iMac Upgrade Discussion Forum

As with previous iMacs there is no floppy drive or high-speed SCSI port for connecting external drives. Instead the iMac has two 12Mbps hot-pluggable USB ports and built in high speed 10/100BASE-T Ethernet. Also included, was an internal 56Kbps modem.

Other changes that occurred with this revision of the iMac, was the removal of the proprietary mezzanine slot and, alas, the infrared port.

Geared for the consumer , school and business market the machine is capable of very little upgradability and is more appropriate for general computer use. The machine came with a substantial software bundle. 

Some complaints were raised by traditionalist about the compact keyboard and the non-standard round mouse. However many new users liked both.

Below you will find the MacBench 5.0 results for all of the current processor upgrades available for this machine. The bar graphs below express results as a percentage of improvement over the base machine, which receives a score of 100%. Further down the page you will find a table with the actual MacBench score.

MacBench Absolute Scores

Processor Upgrade Card MacBench 5.0 Processor Score
iMac G3/266/133/512K 803
iMAXpowr G3/466/155/1MB 1362



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