All AmigaOnes except the G3-SE are fitted with a MegArray socket for a CPU module. This enables the boards to be supplied in varying configurations whilst keeping the cost down. The MegArray connectors are common for PPC processors, however ONLY AmigaOne compatible units will work (limited to those supplied by Eyetech). There are currently three models available, which are supplied with the motherboards and not available to purchase separately (upgrade programmes may be available from your dealer). The current modules are:
- 800MHz G3 (IBM 750FX)
- 800MHz G4 (Motorola 7451)
- 933MHz G4 (Motorola 7455 - supplied as 800MHz units)
There are a set of DIP switches on the modules which are used to control the clock speed of the CPU. The settings for the G4 modules are as follows:
WARNING: Overclocking your processor can damage it and invalidate your warranty. Do not specify a CPU multiplier which will take the processor speed outside its specification unless you know what you are doing and can accept the consequences.
x2 on off on on
x2.5 on off off on
x3 off on on on
x3.5 off off off on
x4 off on off on
x4.5 on off off off
x5 off on off off
x5.5 off on on off
x6 off off on off
x6.5 on off on off
x7 on on off on
x7.5 on on on off
x8 off off on onI don't have the settings for the G3 modules but I'd be happy if someone could send them to me.
Multiplying the FSB speed by the multiplier gives you the CPU clock speed. The default for most modules is x6 which gives 800MHz at 133MHz FSB.
You can find out your CPU model and current FSB and CPU speeds by selecting "System Information" from the U-Boot menu.
The Eyetech supplied fan on most units can be reversed on the connector (JP15) to change the speed (it is recommended to leave this at the default for adequate cooling)