I recently upgraded my hp pavillion dv6000 laptop from Vista to Windows 7. I'm up and running in 64 bit mode but Windows 7 is not making 4gb of ram available, only 2.99 gb. I noticed this when I started getting warning messages that I was low on memory. I checked basic info and it showed 4gb installed but only 2.99 gb used. I thought 64 bit os would see the entire 4 gb of ram.I checked my bios and there is not much to change. Bios shows total memory of 4096mb with version F.2e of bios installed. I checked the performance tab of task manager and it shows the following physical memory: total 3062, cached 1454, available 1639 and free 272. At desktop I'm using 1.38 gb so not much more ram can be made available. Can someone explain what these ram numbers mean? Does anyone have any ideas why this is happening in a 64 bit system. Thanks in advance for your help.