Recently upgraded my PC with a Pentium Q6600 and 4GB (2x2GB Crucial PC2-5300) of RAM. However, when I install the DIMMs my computer only recognises it as 2.50GB? Both of the modules work fine as I have tested them on their own and with the old 1GB DIMMs. Currently have 3GB up and running fine but would like everything up to speed. Have checked MB specs and it definitely supports up to 4GB RAM. Any ideas what the problem could be? Would really appreciate some assisstance.