> On a single user, Windows PC we are seeing about a 1-2 second response to
> return 5,000 rows of data from a single table database with a simple
> SELECT
> query.
> There is some difference in the processing power of the two computers, but
> not that much. The PC is a 2.8ghz Pentium 4, and the Mac is a 500mhz G4
> dual processor box.

Clock speed is the issue here:

In a dual processor environment firebird will only use one processor, so
having 2 processors on the G4 doesnt mean you get 1000MHZ of speed per
thread. Assuming the P4 had Hyperthreading on, the effective speed would be
1400MHZ, vz the G4's 500MHZ, almost 3 X faster. With Hyperthreading off, the
PC is almost 6 times faster.

Keep the G4 for photoshop, and do the real work on a trusty PC :)

.