Does motherboard have a ram limit?

[aram5206]

My wife has a toshiba satellite l355d-s7825 and its a bit date and running slow. Would installing new OS allow motherboard to recognize more than 4gb of ram that it does now? Or is the motherboard setting the limitation?

 

[Platinum Era]

It's the architecture of the OS that limits RAM in your case a x86 (or 32 bit) OS would only use/ allow use of up to 4GB of RAM while a x64 (or 64 bit) OS will limit up to 512GB on Win 8 pro, 128 Win 8 normal, Win 7 basic 8GB, home premium 16GB, and the rest of Win 7 would be 192GB

 

[USAFRet]

It's also the motherboard.
According to Crucial, that has a max of 4GB.