I have one gigabyte of memory using win 7 x64 and core i3-380M, my laptop is oftenly freeze for a couple second when I type a bunch of code also in compilation. I'm sorry for these stupid question, what does precompiled header ?
1 GB seems somewhat underpowered, especially for a 64 bit OS.
If you include large header files, like windows.h, that file gets compiled again and again without having been changed. So you typically put these headers into one "master" .h file, and make this the source of the "precompiled header", preventing it from being compiled again if the contents didn't change.
Both VC++ and GCC have support for precompiled headers.