Burning on sempron sloww

I burning using asus crw 523252 with sempron 2800+ and memory 256 ddr 266mhz.
Why when i burning at 24x the real speed only average @ 16x?
Is amd not designed for burning? because when i use p4 1.7ghz i can burn @24x using the same burner and memory.

Welcome to the forum

Enable DMA

Burning depends very little on your processor, your DMA is probably off.