I installed FC4 on my laptop, but I'm having problems. First, the laptop hung twice while formatting the partition during install (auto partitioning selected). A few days later, I started the install first thing in the morning, because I know I'm having problems when the machine overheats. Installation went fine, but now it's crashing from time to time while working. I'm using LaTeX edited in emacs, and the last crash happened when I opened a Japanese text file in emacs.
About my overheating problems: I also tried installing Gentoo before, but it crashed like hell while compiling, so I went for a precompiled release instead. During Gentoo install, I checked my ACPI code, and there's no errors in it (I downloaded the ACPI VM code from the laptop's flash, disassembled it and recompiled it with the Intel compiler that's more serious about buggy VM code than the Microsoft one. I read about Linux not recognising ACPI as a possible cause of overheating, so I did some exploration into it.)
In Windows, the machine doesn't crash. It still refuses to set the fans to higher speeds, but instead it just slows down the processor.
I have a Medion MD5400 with a 2.53GHz Pentium4. For information on this laptop, check out this link that says so much more about it than I can possibly summarize: http://www.staschke.de/linux/md5400-eng.html