SW: I got a Sonnet 1Ghz last year, upgrading from a Sawtooth 400mhz. The difference is like night and day. It screams. I've had one problem though and its a big one. Sonnet reuses the heatsink that is on top of the old processor. That thing gets scalding hot with 1Ghz beneath it. My machine has 4 HDs in the case along with a Geforce4 Ti. To make a long story short the case got too hot for the chip and it died a couple of days ago. So far my dealings with Sonnet tech support have been very good and I hope to receive an RMA on Monday. If I was you I would pick up a Giga Designs 1.2Ghz chip. Duels don't do much for Pro Tools and if you have a hot case I'd stay away from the Sonnets. The Giga Designs chip comes with a copper heat sink and fan combo on top of the processor. Its like 600 at owc. That is unless you've got a great deal on the Sonnet. You'll be glad you upgraded. -bd

You might want to weigh the used value of your machine + the upgrade cost vs. the price of a new or used Mac at the speed you need very carefully. With the exception of the $300 I spent to upgrade my G3 Powerbook to a G4/500, I've never found it worth it. Plus you risk getting "we haven't tested that configuration" from manufacturers.

I recently upgraded a G4/400 AGP to a PowerLogix Dual 1.25 GHz with absolutely no problem. The difference in machine operations was incredible. The entire upgrade took me about 15-20 minutes. I don't notice any noise difference in my system. Some of the newer machines generate significantly more fan noise. Check xlr8yourmac.com for other upgrade experiences.

i was working with a power mac 9600er 300mhz and a mixplus system, recently i bought a xlr8 g4 450mhz and a sbs 13 slot external pci chassis and a dsp farm, and...everything is working perfectly im so happy, i copuld upgrade for really less money,imagine the price of a new g4...and now i can even add 9 mixfarms or dsp farms, if this should be the case one day,id be very pleased with my sytem,but till them i am satisfied too...but were always looking for more....

I have an Upgraded 400 AGP with a Powerlogix 1 Ghz upgrade on a HD7 rig. Smooth and Fast.