Your comp has to be able to accept the RAM. If it isn't the brand meant for that system, you are only able to access approx. 90% of the RAM output. Nonetheless, Ducky is right. If you computer uses DDR2 these WILL work. Just not as good. Also, if you are unsure whether your system uses DDR2 or not, either look up your system specs online, or open the machine up an look for yourself.