Up for consideration is a rare mid 1990s Intel 486 Overdrive 100MHz upgrade CPU. The Intel spec number is SZ959 V1.1. This CPU has 168 pins and is designed to replace your 33MHz or 66MHz CPU using socket 2 or socket 3. Please note this runs on 5 VOLTS, because it has an internal regulator that gives the CPU the proper 3.3 volts. It is designed to be a drop in upgrade specifically for 486 motherboards that only support 5 volt CPUs. This has 16kb of L1 cache and a bus speed of 33MHz. The original Intel diagnostics floppy is included (not tested). I will package this carefully and ship via USPS Ground Advantage with tracking. Please email with any questions and thanks for looking!