Has anyone experienced sloooooow cs4 rendering

Question

just got our cs4 upgrade (we run 28 copies) .... installed on the 8 engined render farm which is 16gb 8 core xp64, and on a couple of lower specced 3gb 2 core xp32 boxes
doing some rendering tests of a cs3 project, which has 16 similar queued items, which with variations we render every week, so now how long it takes
under cs3
on a single xp64 workstation (32gb, 8core) each item in the render queue takes about 10m
on the render farm (xp64, 8 core, 16gb), because of multiple machines accessing the smae source footage, each item can take like 15 to 18 minutes ... but still happy
on a xp32, 2 core, 3gb machine item will take 35m
on a xp32 single core 3gb machine item can take maybe 1 hr
under cs4
i am getting estimated item times with a minimum of 1.5hrs to 30hrs :-(, same project, same machines ... so its crawling ... similar memory settings, same plugins, but ridiously slow performance

Answer 1

1.) Multiple machines rendering the same footage makes the time required go down, not up.
2.) Purging the cache every 25 frames is completely unnecessary and more than likely slowing things down, not speeding them up. You should be pushing all of your memory to background usage anyway when you are rendering a large queue, which has nothing to do with the cache you're purging.
3.) Your graphics cards have nothing to do with the problem, and neither does multi processor rendering, unless of course you are trying to use OpenGL when you are doing so, I'm hoping that's not the case. Please tell me you are using the rendering engines and not running AE on every machine...
4.) MediaCore is the name of a folder that you install plugins into for Premier and After Effects to share.
You're problem is that you are using QuickTime at all, why would you do that if all your machines are PCs? Try taking the space out of the path (i.e. Week_45) and don't begin your composition names with an _. Your machine had a problem accessing the file it was rendering which is what caused it to fail.
Additionally the settings have changed significantly in AE this time around, it would be advisable to re-familiarize yourself with them all again.
Good Luck