I would like to chime in here. In our practice we have the following:

Amazing Charts is a 3.2 Gigabyte Database
50 Gig of Imported Items.
16000 patient records

Server
Windows Server 2003 R2 Service Pack 2 (32 Bit)
DELL 2900 Dual Core Intel Quad processor (3 yeards old)
4 Gigabytes of memory.
146 Gig 10K RPM Raid 1 (Mirrored Hardisks)
Gig Network Cards (Active on Gig Port)

Desktop
Windows 7 (32 Bit)
Dell Optiplex 780 Intel Dual Core Processor (4 Months Old)
4 Gig of Memory
Gig network Card

We are stiil having the same issues after the 6.10 upgrade. One consideration has to be moving away from MYSQL to SQL 2008 and a Web based client.

We have done all of the hard stuff to ensure we get goog performance.