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Umax SuperMac C600x/240 Processor Upgrade And Discussion Page - Performance Of Latest G3 Processor Upgrades

Umax C600x/240 Facts at a Glance

  • Processor: 603e, 240MHz
  • System bus: 40 MHz
  • L2 Cache: 1MB "Inline"
  • Installed RAM: 32MB, 144MB Max
  • RAM Slots: 2, 168-pin DIMM
  • Min RAM Speed: 70 ns
  • VRAM: 1MB (uses logic board RAM for video)
  • Drive: 3GB IDE
  • Int. Drive Bays: 4
  • Slots: 3PCI, 1 comm
  • Modem: 33.6k (in comm slot)
  • CD-ROM: 12x
  • Introduced: August 1997
  • Discontinued: March 1998
  • Original Price $1,995
  • Current Price

Additional Notes

  • The 16MB of RAM that came with the machine is soldered to the motherboard
  • Supported OS: 7.5.3 - 8.1*

*More recent OS's may work but are not officially supported

SuperMac Upgrade & Troubleshooting
Discussion Forum


The Umax "C" series represented the low end of Umax's lineup. Also in the C series were the C500's which also sported the same 603e processor as the C600's. The C500's, however, used a less expandable desktop form factor. The C600's had plenty of room for expansion with 4 free internal drive bays. Other offerings from Umax included the higher powered "J" and "S" series. The C600x/240 was the first in the "C" series to have Umax's (then) revolutionary cache doubler card. The cache doubler card featured a 1MB cache which communicated with the processor at 80MHz, twice the rate of the 40MHz system bus. The presence of the inline cache boosted processor performance by 26% over the straight C600/240. The cache doubler card sits in the ZIF slot, between the logic board and the processor. Even with this innovative processor design the C600x/240 still featured only 1MB of VRAM which could not be expanded. Those wanting to use a larger monitor and/or higher resolutions would have to spring for an extra graphics card to operate at a reasonable color depth. Like its predecessors, the C600x/240 lacked on-board Ethernet. The internal CD-ROM was a respectable 12x, sufficient to run the bundled software and meet most user's needs quite nicely.

Current processor upgrades for this machine fit into the L2 cache slot and are made by Newer and Sonnet









Below you will find the MacBench 4.0 results for the current processor upgrades available for this machine. Results marked in blue indicate that benchmark results were done by us. All other processor card results were provided by the upgrade manufacturer. 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 4.0 Processor Score

Umax SuperMac C600x/240 481
Sonnet Crescendo L2 G3/240/120/512K 744
Sonnet Crescendo L2 G3/300/150/512K 930
Sonnet Crescendo L2 G3/300/150/1MB 975
Sonnet Crescendo L2 G3/320/160/512K 992
Sonnet Crescendo L2 G3/320/160/1MB 1040
Sonnet Crescendo G3/L2 400/200/512K 1240
Sonnet Crescendo G3/L2 400/200/1MB 1300
Newer MAXpowr G3-L2 400/200/1MB 1415