i have a old power mac g4 digital audio with a bus speed of 133 MHz and a processor speed of 533 MHz. its been good to me for all these years without any problems but i see now that i can buy a powermac g5, dual processor and much faster Bus speed for under $200.00. i could upgrade my processor but not the Bus speed. my wife plays a lot of games online. me, well search engine and itunes. anyway would it be worth it to upgrade for the price. id really like the macpro, but prices are still around $800.00 and up for them. where exactly would i notice the difference between the g4 and g5 ?