Hmmmm.

The one hour thing is interesting.

After a "cold" shutdown, meaning completely removing power from the system (at least for the mostpart) memory should eventually lose whatever was in there before because the capacitors won't be holding power long enough. Could be a memory problem... but you said you removed it and everything was still the same.

Interesting.

How long did you wait after you removed the new memory to see if it boots?

Try that.

Crucial memory is usually top notch, so I don't know. But bad memory is fairly common.