9 sockets suggests 256KiB 8+1 setup, most likely dual-bank capable. Most mobos also allow smaller cache with only one bank populated like 128KiB, or even 64KiB or less - that also uses smaller tag chip, but it's usually a 386 thing and 486-only mobos tend not to go below 128KiB. My point here is, what chips you need depends on what you want as well as what the mobo supports. In general you'll need 8x 5V 32KiB chips for data (20ns or better, preferably 15ns) and, for 256k 2-bank setup, also another 5V 32KiB chip for tag that's 15ns or better (preferably even 12ns or 10ns if you can get one).

PeterTheWomble wrote on 2022-01-26, 13:12:

A google search turns up chips which look like they'd fit available from mouser.co.uk. Is this likely to be the right stuff, are they really still in production?

In case you are talking about the IDT 71256SA series chips at mouser, they should work. 15ns would leave more room for good timings bus speeds above 33MHz than 20ns, but availability (check stock and lead time!) is poor. The price seems OK for new stock bought via a reputable distributor.