Presario SR1109NL 1GB PC3200 DDR Memory Compaq Presario SR1109NL RAM -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)