Thinkpads Forum

Hi everyone!

I would like to buy math coprocessor for Thinkpad 700c. Please, reply if anyone has them for sale. Thanks in advance!

I believe the 486 slc 25mhz cpu uses a 387sx FPU. I probably have one, either the Intel or the Cyrix version but I doubt I'd be able to find it any time soon.

A photograph of the socket would be helpful to help identify what chip you need.

Good luck

Thanks for the reply!

It is 387SL but as far as I know, 387SX will work too.

http://www.pc-atrium.de/html/koprozessorenintel.html

It is last but third image.

Hello,

I have a math coprocessor in my old faithful Thinkpad 720C back from 1993
I bought it because I needed to run a math coprocessor-intensive software (I think it was AutoCAD)

It was not an Intel version however, I think those were either horrendously expensive or unavailable anywhere at that time.
It is an IIT 3C87SX-33 - and it is available, it has been quiiite some time I don't run anything math-intensive on my 720C

Here is a link to the picture I took a couple of minutes ago :
https://www.dropbox.com/s/csbalkae2ugxptp/IMG_1402.JPG

I might add it does run on a 700C, it was originally in my own 700C before being transplanted on the 720C that replaced it

Thanks for your response!

Would you sell your 700c and/or 720c ?

Please, let me know.

Thanks in advance!