This is a site heavy in DHTML and IE6 takes a while to render on slower CPUs.
The next version we're talking about having a "Low Bandwidth" version, that would be for slower computers as well.
For now, try FireFox. It tends to process CSS much much faster then IE.
On my 4.2 Ghz machine, I can't tell a difference though between IE and FF. :)
Thanks!
Eric A. Duncan