Problem with laptop ram upgrade

[chkontog]

Hi, i installed 2×2GB PC-6400S sodimm memory on my laptop and it doesn't work.When i put one of memory it works.Also i put the 1×2GB with an 1×1GB memory and it works again.Do you know what is the problem?

[KFerrabelo]

which model Presario C700 do you have?  https://www.crucial.com/usa/en/upgrades/hp---compaq/presario-c700-series

Also, when you have the 1×2GB with an 1×1GB memory configuration, does the bios read 3 GB?

[Huffer · Accepted solution]

Officially 2 gigs is the maximum memory on that model series but it will run 3 gigs OK. You are seeing a limit in the capabilty of the chipset and BIOS. It will not run 4 GB of memory. 

[chkontog]

thanks for your reply 🙂