I added correct memory and after that the PC will not even power up. I did the basic trouble shooting. Remove the new memory. Swaped the meory around. Checked all the connection and incoming pwer, and checked the power out of Power supply. I do have 5V but no 12V.
PC only has soft start, so I don't know if the processor would tell the PS to turn on or not. Because nothing works, no fan, nothing. I removed the battery and drained the CMOS as well. Still nothing. The only thing I noticed is a blinking green light in the back of PS which used to be solid green when it would properly come on. I do get the solid green if I disconect it from the mother board.

Please help..... Thanks

Check your main atx power plug into the MB. wiggle it allitleto see if the ps light goes solid.
Mine was bad, so i replaced MB and PS. Problem solved.