Pentium II Upgrade
Silver Surfer
My research on this subject all over the Internet has produced a mixed bag
of information. Apparently the issue is not easily addressed, or else I
haven't yet found the right place to inquire.
My ThinkPad 390E is equipped with a Pentium II, 300 MHz processor in the
MMC-2 package. It appears to me that several faster Pentium III processors
are available in the MMC-2 package. Can I drop one of the faster PIIIs in
my machine and expect it to function properly and to produce a performance
gain even if it's going to be underclocked in my existing system?
The PII has a bus speed of 66 MHz while most of the PIIIs have at least a
100 MHz bus. The bus to core ratio of most of these is locked. I assume
that my motherboard will continue to supply the processor with 66 MHz.
Therefore, to get a performance gain a PIII would have to be in the 700+ MHz
speed class (core ratio of 7.5 times 66 MHz bus = 495 MHz). Otherwise I
would be just as well off to get a 400 MHz PII.
Intel won't discuss their obsolete products. Same with IBM. Must be
someone knowledgeable out there who can help with this matter.