So heres the problem: Whenever my computer is stood on its legs, the way it is supposed to be, then if my desk is shaken or i stamp on the floor it will lose power immediately, as if the plug were removed. i have been told this could be a problem with the earth connection but i have tried all i can think of to solve this issue. I am using all of the correct connections and screws for my motherboard and i have tried replacing the power supple and the cable. the only 2 things i can think of are the face that the case is missing a leg after it was broken off (however i cant think of how this would make much difference) or the case its self is very cheap.

The case may be flexing if only three feet are on the case. This can bend the MBoard, which is not good. Fix the feet and be sure to have all covers for the cas installed with screws.

ah thank you, well ill be getting a new case in about a week which i thought might fix it, so if that is the problem then thanks and ill let you know if the case helps

Cases are designed to accomodate multiple MBoards. The threaded standoff holes may not all be used with a particular MBoard. Care must be taken to install standoff in every place there is a mating screwhole in the MBoard and ONLY in those places. You current issue may be due to a stray standoff that is intemittently touching a part of the MBoard where it shouldn't. FYI it is possible to break a MBoard if the standoffs are not used as designed. The pressures exerted when installing things like RAM and video cards can do it in. When that happens you can have a break in a trace and that could also cause your problem. I am not suggesting your board is cracked.

The standoffs i have used came with the motherboard and are all screwed into the correct holes, i doubt this is the problem but ill will double check just in case, also i have only installed new RAM recently and the motherboard worked before after i installed the original RAM, it is more likely to be the case, it is cheap and the new one will be of much better quality