You can remove the mobo from the case and try it on a wooded or glass surface. Do this only if you are comfortable with taking your system apart! I always use rubber washers between the board and the case as a precaution. Make sure the video card is seated correctly in the slot and the power plug is in and locked down.
As for the psu calculator, in Windows go to Start>Run type in dxdiag and run the diagnostics. It will give you enough info to help out, cpu brand, amount of ram, etc. Come close and see what you get.