1999 Sonnet Crescendo G3 400MHz 1 MB Cache Upgrade card 
BG3-400-1M for Power Mac 6400 6500 5400 TAM


The Crescendo/L2 G3 400 MHz CPU Upgrade for Power Macintosh and Performa from Sonnet is processor upgrade for Power Macintosh and Performa computers. The processor plugs into the L2 backside cache slot to give it G3 processing power running at 400 MHz depending on the system bus speed. This is a great way to breathe new life into your older Mac computer.

Power Macintosh and Performa Compatibility
This processor upgrade is compatible with the following computers: Power Macintosh 4400, 5400, 5500, 6400, 6500 and 7220; Performa 54xx, 6360 and 64xx; Twentieth Anniversary Macintosh; PowerBase Desktop and Minitower; Starmax 3000 and 5000, Umax C500, C600 and C600X. It will function at a 400 MHz clock speed in all systems except the Power Macintosh 5500 and 6500 and the Twentieth Anniversary Macintosh. 

Simple Installation
The upgrade installs easily in your computer's Level 2 backside cache expansion slot. This innovative design allows you to upgrade systems that did not feature processor upgrade slots. The installed Cache Doubler must be removed from the Umax C600X in order to install this CPU upgrade.
Mac OS Compatibility
The processor upgrade is compatible with all versions of Mac OS from 7.5.3 to 9.1. It is not compatible with later versions, including Mac OS X.


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