Intel OverDrive ODP486DX-33 SZ802 CPU Processor
BOXODP486DX33SZ802 is the retail boxed part number for the vintage Intel OverDrive ODP486DX-33 central processing unit (CPU).This piece of computer history was designed as a drop-in upgrade processor for early 1990s IBM-compatible personal computers. It allowed users to significantly boost their system performance without replacing the entire motherboard.
Core Specifications
Processor Family: Intel i486 (80486)S-Spec Number: SZ802Core Stepping: B1Internal Clock Speed: 66 MHz (Clock-doubled internally)External Bus Speed: 33 MHzL1 Cache: 8 KB Write-ThroughSocket Type: 169-pin PGA (Pin Grid Array) for specialized OverDrive upgrade socketsOperating Voltage: 5 Volts
Key Features & How It WorkedClock Doubling Technology
Though the part number says "DX33," it actually operated as a 486DX2 running at 66 MHzIt took the motherboard's existing 33 MHz system bus clock and doubled it inside the chip. This accelerated math calculations and software processing while staying compatible with older motherboard hardware.
The Upgrade Layout
The "ODP" designation stands for OverDrive Processor. This specific version featured an extra 169th "sense" pin. When plugged into a designated secondary motherboard upgrade socket, it automatically shut down the original CPU (often a soldered 486SX) and took over all computer operations.
Integrated Math Coprocessor
Unlike the cheaper "SX" branded chips of the era, this chip came with a built-in Floating Point Unit (FPU). This math coprocessor was vital for speeding up spreadsheet calculations, early computer-aided design (CAD) programs, and demanding 3D video games like Doom