Is a laptops maximum RAM capacity a physical hardware limitiation or can it be overcome by upgrading the OS to 64-bit...
I have a Toshiba (Satellite A305D-S6848) laptop with the 32bit Vista OEM pre-installed. The manual states "Maximum capacity 4096MB". If I upgrade the OS to a 64bit, will this allow me to overcome that 4GB limit or is that limit a physical one stopping me from ever installing more than 4GB's of RAM?
RAM capacity is a physical hardware limitation.
32 bit limited to 4GB = 2^32
With a 32-bit OS you may only use around 2.5-3.5 gigs of memory.
Some parts of the system of memory is used for hardware reserved or integrated graphics.
To take make full use of 4GB RAM installed you need a 64 bit OS and a 64 bit compatible CPU.
Your laptop CPU is 64 bit and If you have 4GB RAM(the maximum amount) installed all you need is a 64 bit operating system.