Motherboard Help Pages
4.I have bought a Cyrix MII 300
and I have set the motherboard to 3x100 (100MHz bus and 3
times multiplication factor) but it won't run at all. What
should I do to get it to run?
All Cyrix MII processors have their speed quoted as a benchmark
comparison and not at the actual speed that the processor
runs. The idea is basically that although it does not run
at 300MHz it is on average as fast as an Intel Pentium 300.
In practice most people find the Cyrix processors performance
to be more in line with the actual processor speed rather
than that of the quoted benchmark. However there are quoted
benchmarks that do support the supposed higher figure. As
a general rule the Cyrix processors are the cheapest to buy
and tend to be used on the cheapest motherboards in budget
systems and this may well account for this difference.
The Cyrix MII 300 came with
3 settings 3.5x66 (233MHz) 3x75 (225MHz) 2.5x83 (207.5MHz)
These were always wriiten on the Processor and it should run
satifactorily at the stated setting. However in addition it
is important to note that some other parts of the system that
the processor is in may find settings other than 66MHz to
be unreliable (for example PC66 ram may give rise to fatal
exception 0E errors or invalid page fault illegal operations)
and so running at 66MHz may prove more stable. Some people
find the 66 bus setting to be the most stable and use it to
stabilise problem systems that were apparent when set for
the 83 bus setting (even though 83 was quoted on the processor).