What would be best

Im running a G4 dual 1.25,2 gig of ram & running heavy photoshop processes and seem top be running out of memory a lot, My Nikon D3 & D300 files are so big Im having problems handling them, Im thinking of Upgrading to a Mac Pro, here is the question on Ebay I can get a dual quad core 2.8 with 320 gb hd and 2 gig of
ram for around $2500. or I can get a similar configured 3ghz for around 3,000
I would like to stay under the $3000. mark so I can add some ram and hard drives, would I notice a big difference in the 2.8 compared to a 3ghz, all other things considered equal ram & hd? Thanks for the info. Im also considering wiping the G4 which I have 2 of and installing Leopard as a clean instal, I think that would help but kind of have my mind set on a new one that will let me add more ram
Dennis

The apple refurbished site might be just what you're after. Just check back there often. As the site is often updated with more computers there. And it's much safer than ebay. Even right now they have quite a few good Mac pros for around your $3000 mark.

And the difference between 2.8 and 3.0 and even 3.2 is not really noticeable under must normal circumstances. Even with multiple apps running. Sure your video might encode a toucher quicker but that's it. Actually for heave video/photo editing or game playing the GPU would be more worthy to look into.

Apple Refurbished (US).
http://store.apple.com/1-800-MY-APP.../RSLID?sf=wHF2F2PHCCCX72KDY&nclm=CertifiedMac

Thanks thats what I thought, sometimes I look to get the best available but my budget doesnt allow me to I have been watching the refurb but just not ready to buy today, What is the GBU ? Im not familiar with it, Im hoping to get a Dual quad 3ghz and add about 8 gigs of ram and a few nice medium hard drives, Ive gotten about 5 years of excellent service out of the G4 so I hope the next one will last that long