how come i only have 2.94 usable Ram out of 8gb?

Most likely because you didn't read your mobo specs to see how much ram each slot could take! You don't just buy ram and poke it in without checking your particular mobo specs. Secondly, if you only have a 32 bit version of windows, you can only max it out to 4 gigs.

Because you are running Windows 32 bit version. Windows 32 bit version only recognizes up to a maximum of 4GB of memory (RAM). It does not matter if you add more RAM. It only recognizes a maximum of 4GB.

Windows 64 bit version, can recognize over 4GB of RAM.

Click, Start, All Programs, Control Panel, System, then System. It will tell what version your Windows and if it is 32 bit or 64 bit.

Are you using a 32 bit computer? They can only have 4 GB of RAM. So, since you are 32 bit, you are unable to use the stick that you bought.

the operating system is most likely 32-bit. 32-bit operating systems can only see a max of 4gb of ram (this includes video memory) so you will have to install a 64 bit operating system to use more then 4 gb of ram

first of all check that your computer is hsowing that you have 8gb ram. i am sure you have alerady done that. then go to windows task manager and check how much of ram is being used by all services. if youstill face problem then install a program which helps in freeing up the ram(lots are available freely on net). try freeing up the memory.still problem try loading windows XP. still problem call up HP customer care..thats all i can think of...hope it gets sorted out.

32bit OS won't locate extra memory than 4GB. Your board is utilising device memory for video memory, this brings your finished to 3.5. you would be able to desire to enhance to a 64bit os and ideally a extra efficient video card.