Note: Some For motherboards can be used but display 4GB Voltage: DDR2 1.8V Dual Channel:Support Pins of Memory DDR for Desktop=184 pins DDR for Laptop=200 pins DDR2 for Desktop=240 pins DDR2 for Laptop=200 pins DDR3 for Desktop=240 pins DDR3 for Laptop=204 pins Read First The Recognition of XP is around 3GB The Recognition of Win 7 32Bit is around 2.26-4.5GB The Recognition of Win 7 32Bit is around 8-16GB Before purchasing , please confirm which model is suitable for your Desktop/Laptop, usual models are as bellow: PC2 4200 = DDR2 533MHZ PC2 5300 = DDR2 667MHZ (Compatible with DDR2 533MHZ) PC2 6400 = DDR2 800MHZ (Compatible with DDR2 667MHZ, DDR2 533MHZ) PC2 8500 = DDR2 1066MHZ size:Length: 13.3CM Material:PCB colour:Green Package Contents: 2 x DDR2 RAM Memory Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. Full Tested. Capacity:8GB Speed: DDR2 800MHz (PC2 6400) Number of Pins: 240 pins Type: Memory Ram