Business Desktop d530 Ultra-Slim Desktop Samsung 1GB PC3200 DDR RAM Memory for Compaq Business Desktop d530 Ultra-Slim Desktop-1Gb 1024MB 128x64 PC3200 400MHz DDR DIMM non ECC 2.5 volts spec CL=3 latency.Most machines require this memory in matching pairs.Buy and install in pairs (for a pair OR kit please buy quantity 2)