That can't possibly be right - I have a rather ancient P4 (1.3 GHz) that's currently running a Tinker unit at 14 minutes per frame. No way a 2GHz Athlon should be taking that long - it should be running in the 6-7 minute range at worst. Something's stealing cycles somewhere.
The 400 frame Tinker units take:
8 mins on my 1.2GHz Athlon 4 Palomino Laptop
15 mins on my 700MHz Athlon K7
32 mins on my 500MHz Pentium 3 Katmai
Thanks for the comments. I thought there might be a problem, but wasn't sure. Think I'll try shutting down all the background programs for an hour or two to see what happens.