Totally incompatible I'm afraid, both physically AND otherwise
(electrically they use a totally different bus).
You MIGHT be able to upgrade your socket 7 board with a K6 processor,
they were made at speeds up to 550MHz as I recall. However it's quite
doubtful that you would be able to use the fastest K6 chips in a board
that originally housed a P200MMX. In fact, chances are you're pretty
much SOL in terms of useful CPU upgrades for that board.
The top multiplier K6-X supports is 6x (set jumpers to 2x, the chip
interprets it as 6x). If the bus speed of the board tops at 66, you
are stuck with 400MHz - still better than p200mmx. With 75MHz bus
option and a bit of luck (IDE controller and PCI and AGP, if any,
cards may or may not tolerate this overclock) it comes to 450. If
there is the 83MHz bus option, and assuming the PCI/AGP devices take
it, it comes to 500 - nothing to write home about these days, but
already acceptable for basic MS Office work and web browsing under
Win2k/WinXP, assuming there is enough RAM (256MB at least). And in
case this board is of SuperSocket7 type (quite unlikely - it would
rather be already running some sort of K6-x instead of P200MMX if it
was one) and it has the bus speed 100MHz available, you may try your
luck with one of K6-2+/K6-3+ chips. These chips can go all the way to
600MHz with a bit of luck, and they have on-chip L2 cache that also
helps quite noticeably (I even used one of these for a while to run
Visual Studio .NET, and it was tolerable). The board may or may not
have the core voltage settings required by K6-x, but these chips
tolerate overvoltage quite well with adequate cooling.
Having said all that, I still suggest to replace the board with
something more contemporary. Even the cheapest Sempron will be leaps
and bounds ahead of anything socket7 is capable of. Of course this
will result in the need to replace the case and PSU (the current one
hardly is ATX, much more likely older AT type), and RAM (the old board
probably runs PC66, maybe even EDO, but surely not DDR).
