Here is what benchmarks I could find on the net:

http://lowendmac.com/ppc/g3card-mb4.shtml

Using MacBench 4 on my 8600/300 I get 728 for CPU and 775 for FPU under OS 8.1.

Looks like 950-1000 is the score 300 Mhz G3's get for CPU depending on the cache (512K or 1MB) no idea what FPU would be for 300 Mhz G3s.

Just for the heck of it I ran my Beige G3 MT (433 G3 1MB cache) on MB 4 and got 1443 for the CPU and 1081 for the FPU.

Anybody have a G3 300 512K/1MB cpu in a PCI mac to compare? I can email MB4 to anybody who needs it.

I would think FPU wise a 604EV at the same clock speed is comperable to a G3 at the same speed.