I have a Matrox RT2500 running on a Dell 340 Precision. I am exporting my timeline as MPEG II for eventual placement on DVD. I am using the Matrox export default settings. Why is it so slow to export this stuff. When I look at what is going on in the system using the performance monitor, I don't see where the bottleneck is. I have plenty of memory available, cpu spikes up to about 40%, reads spike to 100% but are not constant and writes spike up to about 50%. Nothing seems to be pegged at 100% to indicate a bottleneck.
I've done some experiments with disk to disk copy and I have way more bandwidth available than what is being used by Premier to export this stuff.
If you're using the Matrox MPEG2 IBP export, then you're tied to the C-Cube chip on the RT2500. On my 700 MHz PIII, I ran at about 3:1. I preferred the quality of the Ligos LSX-MPEG plugin, though, which ran at 5:1, when transcoding an exported (and fully rendered) clip.
That's why I bought an RT.X100, so I'd get realtime export from the Premiere timeline.