I've been using my tower at home more and more to edit and was running into some performance issue when I have both Motion & FCP (7) open. If I shut down Motion then reopen FCP frame rate goes back to normal (29.97 or 23.97) I seem to recall someone posted a way to clear the RAM cache which would be good to know; but probably more RAM and perhaps a beefier video card might be the ticket.
More RAM will likely help. If you have Motion open, and you've performed a RAM preview, you might have taken up all RAM and disk caching starts... ugly. Get another 6 gigs of RAM and what your experiencing will likely go away.
Adding a beefier video card is going to make Motion run better for sure. Might check out the reviews of the upgrades available for your Mac at http://www.barefeats.com
8-Core 3.0 Intel Mac Pro, Dual 2 gig G5, AJA Kona SD, AJA Kona 2, Huge Systems Array UL3D, AJA Io HD, 17" MBP, Matrox MXO2 with MAX - Cinema Displays I have a 22" that I paid 4k for still working. G4 with Kona SD card, and SCSI card.
Another consideration: the OTHER software you like to use on this machine.
do you routinely run any other multimedia-creation software other than that associated with Final Cut Suite, e.g. any Adobe applications? Do you like to have a browser open, do you like to have Microsoft Office for Mac open, etc.? You'd want to figure them into the mix, too.
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