Can I ask that you only post back when you have finished all testing and so have all of the test results, I never got any notification of your replies #22 and #23 as you were replying to your own reply #21
One minute is nowhere near long enough I`m afraid and what you ideally should have been doing was to use the computer as you normally would albeit with only the one stick of RAM inserted, below is my canned info for properly testing the RAM;
How to physically test your RAM.
The following checks require the computer case to be opened so take the following safety precautions 1st, disconnect the power cord from the wall socket, press the case power button for twenty seconds or so to get rid of any residual charge in the system, take anti static precautions before touching anything inside, you can do this by touching a bare metal part of the case or PSU or if a notebook by touching a household radiator or associated copper feed pipe.
Have a pencil and notepad to hand.
Remove each stick of RAM and blow out the memory slots.
Insert the first stick of RAM in memory slot one, reconnect the power and in the case of a desktop computer the video to screen cable.
Power up the computer and see how it goes.
Make a note of the results.
Repeat the procedure until the first stick of RAM has been tested in each memory slot and the results written down.
Remove the first stick of RAM and put it to one side on top of a piece of paper with the number one on it for identification purposes.
Repeat the procedure with all RAM until each stick has been tested in all slots, the results written down and the sticks identified numerically.
Now the really long winded part;
If no individual stick of memory or slot on the MB has an obvious problem all of the above needs to be repeated but this time by running
Memtest 86 for each stick of RAM and in each slot on the MB and for at least 4/5 passes, for some reason that many of us cannot explain a stick of RAM may work in one slot on a MB but not in another.