installing memory and heard snap and burn smell when powered back up.thought might be psu. cpu fan is running, HD does not powerup. Antec 400w about 2 years old
More aboutsnap burn putting memory
Run through the checklist at the top of the forum about boot problems first.
IF you can smell, its bad. Look carefully at all components (motherboard, PSU, graphics card, ram, etc for signs of discoloration. Often you can see the damaged component. Also move the parts away from each other and you may be able to smell it.