Kingson is right to the extent that there is a lot of RAM out there that won't work in Macs. There are plenty of people on these forums who can attest to that. But their RAM isn't the only RAM that is guaranteed to work.
You could put 8 sticks of that in your PowerMac (as in, it would fit). No idea if it would work, or cause frezes/kernel panics down the line.
I'd pay the premium for Crucial (
linky for your PowerMac), after currency conversion its $159AUD+tax.