Memory sticks, 32 and 64 Bit OS
Will Windows 7 32 bit edition support 8 GB RAM? or it will only support 4 GB.
Will i have to buy 64 bit version if i want to use 8 GB RAM?
This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.
32-bit operating systems only support up to 4GB (actually less) of RAM. So yes, you will have to get the 64-bit version of Windows to use 8GB of RAM.
There are some hacky ways to enable more than 4GB of memory on a 32-bit machine, though. For example, you can use PAE (Physical Address Extension), but that's slower than simply installing a 64-bit OS. There is a kernel patch that enables this for Windows 7, but I wouldn't recommend it: it's risky and not worth the trouble when you can just install the 64-bit version of Windows.