Very Computer

Hi,
        I come from an HP-9000 background.  HP has extensive hardware
diagnostics.  Is there any such thing for Linux on Intel???  I've heard
of a memory test, but that is just one thing I would like to test.  I'm
having sporatic freezes with no error messages logged whatsoever.  It
may be memory, but it could be CPU, motherboard, SCSI controller (Adap)
or many other things.  I would even pay (ouch) to have such diagnostics.

Thanks