lshw (Hardware Lister)
is a tool used to provide detailed hardware information on your server's hardware. It can report exact memory configuration,
firmware version, mainboard configuration, CPU version and speed, cache
configuration, bus speed, etc.

On Redhat you can install using yum from the Dag Repo. Using the command below you get both the command line version and the gui.

yum install lshw-gui.x86_64

Then launch it with lshw-gui, or run the command line version with lswh. You can also dump your output to a file. In the example below I am dumping out to an html file

lshw -html >MyLinuxBox.html

More information here http://ezix.org/project/wiki/HardwareLiSter