>Are the "Pentium" upgrade chips that fit a 486 socket worth buying? This is a workstation with 20 megs of memory on a Novell Network running a 2.x application. Eventually we want to mix in new VFP programs. There is no money right now for a $400 motherboard, power supply, and memory upgrade.

There are at least three upgrade chips marketed that might be useful, Intel's DX-4 and Pentium Overdrive for the 486, and the AMD enhanced 486 processor. My experience is that you're more likely to be able to install the AMD processor; the requirements for the Intel POP as far as socket, voltage and BIOS are not as likely to be there, especially on a machine running a DX-50. The DX-4 is a clock-tripled/clock doubled processor (if you run it at a base CPU clock of 33MHz or below, it's clock tripled; above that, it's clock doubled) will work in most 486 boards that support at least the DX2/66 processor; again, it might require a BIOS upgrade or an additional voltage regulator. The AMD is a clock quadrupled processor with an enlarged L1 cache; it has the best chance of working, especially if you buy one as a part of one of the commercial upgrade kits like the Evergreen kit.

An upgrade to a Pentium motherboard should not cost $400. You should be able to buy a GOOD Socket 7 (Pentium) motherboard with processor for $200 or less. 32MB of memory should run in the $50 range. Unless your power supply is known bad, a Baby AT form factor motherboard should work fine with your existing supply for the 486. If you havne't talked to a mail-order vendor, try http://www.pcnut.com; they have the SuperMicro P5MMS98 and ABit AX5 motherboards in stock. They have barebones systems (motherboard, 32MB of memory, case, power supply, floppy) for $280-290 depending on board, and you could then add a K6-200 for about $80. Buying just the motherboard, processor and memory would come to about $235 (if you do this, make sure to get the Baby AT form factor board, since that's what's used in most older cases). This is going to get you a whole lot further than a processor upgrade for your 486 which is going to cost in the ~$100 range.