I have heard that some A1200's have problems with PowerPC
cards. How do I know if my Amiga will have problems and how can it
be fixed?
The problems occur on A1200's that use the 1.D.4 and 2B
motherboards. You can find the board revision by looking inside
your A1200 on the board. These include some of the later Commodore
and all Escom systems. If you have one of these boards you will
encounter problems when adding faster processors, serial, Zorro
devices, etc. These can be fixed by taking the motherboard to
Eyetech (http://www.eyetech.co.uk), who
charge £30, or Power Computing who can perform the "downgrade"
for £20. If you fancy trying to fix it yourself information on
the upgrade can be found in the A1200 Hardware Guide, available on
Aminet at hard/misc/A1200Hardware.lha. The relevant section is
shown below:
*_Motherboard Modifications_*
As with most machines, the A1200 left the factory with a few
design flaws.
Most of these won't affect anybody, but they can stop some
accelerators
from working. Here are the modifications that should be made for
a
"perfect" A1200;
*REV 1D.4*
Budgie REV -01
> Remove E123C and E125C from the A1200 motherboard
Budgie REV -02
> Remove E123C and E125C from the A1200 motherboard
> Remove XR358 470 ohm pull-up resistor
> Add 470 ohm pull up resistor at pin 43 of U, ie the Alice
chip
*REV 2B*
Budgie REV -01 and -02
> Remove E123C and E125C from the A1200 motherboard
> Add 470 ohm pull-up at pin 43 of U2, ie the Alice chip
> Change R118 from 470 ohm to 220 ohm
BACK |