Unstable XP 2600+ with MSI KT4V

Question

Hi
I've just slapped together a new setup with a XP 2600+ Thoroughbred with a KT4V.  It as a working stick of 512 PC2100, an new 450w psu and a couple of  old hard drives.  It becomes very unstable when I run it at 166 but okay at 100, but this reports an unknown athlon running at 1.25.  Any help appreciated.
Taff

Answer 1

pII box??
Here is something that works and that I push on to people in your situation:
Reseating time
You need:
a star shaped, Philips screwdriver, and an ordinary flat one
strong, preferably chemical alcohole and/or Acetonic
a tuss of cotton
clean, preferably dust free cloths
thermal grease, preferably Arctic Silver
good light and a large kitchen table
some patience
a vacuum cleaner, preferably reversible, of a can of compressed air is not bad.
Pull the power cable out, and disconnect mouse, keyboard and such cables from the rear.
Put the case with the open side up on the kitchen table or similar. Have a newspaper under to prevent scratches.
Disconnect all cabling and possible AGP- and PCI-cards from the motherboard. It isn't absolutely necessary, but you might as well take the memory out too, as it will give you more freedom later.
With a philips screwdriver /star shaped/ unfasten the motherboard. When lifting it out I normally use the heat sink. Lift slowly.
Put the motherboard beside the case on something a bit soft, a cloth or a thick newspaper. Use an ordinary, flat, screwdriver to unfasten the heat sink. You push a clip down, and when that is loose it's easy to lift the heat sink off.
Clean both the bottom of the heat sink and the processor chip from old thermal grease. This is important! Strong alcohole and oil free Acetonic and a tuss(?) of cotton are good for this. After the cleaning, dry with a clean cloth.
If it is possible, use high-pressure air to blow the heat sink fins free of dust.
Make a note of the model no. on the processor.
Put the processor back on. Add a small drop of new thermal grease on the very chip of the processor. The drop might be half the size of a corn of rice. Spread it out with a plastic card: American Express Gold. 
Make a virtual seating of the heat sink, so you are sure where to finally fasten the clip.
This might sound like a major task, but when prepared you'll do it in about fifteen minutes.
Before putting the motherboard back, you might have a look to see if the case needs some dry cleaning. Also have a look at the PSU and the cards. Don't use anything than air.
Here is some additional, illustrated, guidance:
http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/23986.pdf