MB with multiple personality disorder

MB: MSI K9NGM4
AMD Phenom 8650, Triple core processor 2.30GHz
3.25 GB of RAM
NVIDIA GeForce 8800 GT
OS: Windows XP SP2 on SATA drive
DVD/CD-ROM on IDE master
second HDD for additional storage on IDE Slave (I know, I know)
USB cordless mouse, etc., etc.

For some weeks I have been experiencing the following issues:

Graphics card will not be detected (fan spins, but no signal to the monitor) so I need to use the integrated graphics, no fun for gaming.

Graphics card is detected, and then will run fine for days and then back to not being detected again.

IDE master and slave not detected (both in the BIOS and the devise manager).

The above drives are detected and will work fine, as with the graphics card, after some re-boots they are mysteriously not detected again.

CHKDSK always runs on the secondary drive (which has 2 partitions, so E and F).

Everything will be working fine, then the USB mouse will freeze up requiring a restart after which I usually experience the above problems, which eventually right themselves.

Systems hangs while posting (I think) on “initializing USB controllers” sometimes for 20-30 minutes, sometimes for a few seconds, other times not at all.

I didn't build this system, but it did work well for about a year without any trouble, per the above configuration. I added the secondary drive and have un-installed and re-installed the graphics card many times and researched the various issues to death.

I never know if a re-boot is going to be clean, when it is great, when it isn't I need to go back to on-board graphics and may be without a couple of drive.

Question(s):

Is the motherboard shot?

Is there a hardware diagnostic tool (for a noob like me) I can run to test the various components?

Any sage advise is appreciated.

I found your problem, your hitting the bong too many times per hour.

See if there is a motherboard bios update that might address any of your symptoms.

To test the ram, download memtest86+. It should run a full pass with NO errors.

To test the cpu, run prime95 long enough to get the cpu to a maximum temperature.
Use the option to check for rounding errors. There should be NO errors.

Go to the hard drive vendor's web site and download their diagnostic package. For western digital it is called "data lifeguard"

Is your PSU old, or of suspect quality? A bad one can cause strange problems.

Sometimes a faulty USB device can cause strange problems. Try substituting for the mouse or keyboard if you can.

Drivers don't cause vertical lines on the screen at POST.

Drivers can't help since they are loaded with the OS. I may be wrong, but your video card is most likely defective. Try another card to see if it resolves the issue.