AI Overview

Some older ASRock motherboards, particularly those designed for Socket 478 Intel Pentium 4 CPUs (like the PE PRO-HT, GE PRO-HT, G PRO), were built with special chipsets (e.g., SiS 645DX, SiS 651) that featured both SDRAM (PC133) slots and DDR DIMM slots on the same board, offering users flexibility to use either type (but not together) to save costs during the transition from SDRAM to DDR memory. These "combo" boards had distinct physical slots for each memory type, allowing for mixed generation systems before DDR fully took over.

Some older ASRock motherboards were specifically designed with separate slots to support either DDR2 or DDR3 memory (not both simultaneously), such as models in the G41 or N68 series, allowing users to choose the RAM type for their build, but physical notches and voltage differences make DDR2/DDR3 RAM physically incompatible for use together in the same board.