Some G3 and G4 processor upgrades for beige macs from the 90s have dip switches for setting the processor and bus speed, as well as a special switch for when you install it in a PowerBase (a clone). With so much information falling off the internet and getting harder to find, I thought I’d post the settings for some cards here.

PowerLogix PowerForce G3 Speed Settings

This is what my PowerLogix card looks like, it is a 400MHz, 1MB Cache G3 (PFG3 400/200/1) upgrade for PCI macs with the processor slot, for example things like the 7500 to the 9600, and some clones.

Here are the settings :

XLR8 Mach Speed Settings

The following settings apply to a number of XLR8 cards, including Mach branded cards. The first 8 switches seem to control the host bus speed, the remainder set the CPU multiplier.

You can also additionally set the Backside Cache speed using XLR8s software.