1200HD/A (250-3000/A) Math Coprocessor Faxback Doc. # 1965 Note: Refer to Faxback Doc. # 1277 for Main Logic Board Layout for installation location. There is a socket on the main logic board at location U3 for the math co-processor. Note: Refer to Faxback Doc. # 1962 for Jumper change when adding a Math Coprocessor. Note: Refer to Faxback Doc. # 9002 for Catalog Number for a Math Coprocessor for your computer. Contact the nearest Radio Shack Store for the purchase of a 5 MHZ Intel 8087 Math Co-Processor.