300/400 is MHz of your RAM.4x-5x ect... Is your CPU multiplier (usually locked by the CPU (not really adjustable anymore these days))
Then it seems that you adjusted your FSB (which is the only way now-a-days)
However you have to watch what your expansion BUS is running (PCI=33.33MHz) and your AGP runs usually same as FSB.
The only thing you can do to stabilize your system is to bump up the voltage of either the RAM or the CPU (one at a timne in least amount of steps).
Asside from that, I don't know what your asking?
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