I was upgrading my video card in my HP Pavilion p6115y desktop to a GT430. My monitor displayed the BIOS correctly, and then it would say no display as it started to load windows. A few reboots later, it would load windows, and then the display would turn off again (on lcd as well as tv). I was in the middle of installing new drivers for the video card when the display cut off one more time. I let the computer run in the background to finish installing the drivers. A few minutes later I come back to the computer to find that it's turned off. I tried to start it back up again and noticed a burnt smell by the motherboard and PSU. I tried to reboot the computer and the fans would spin for 1-2 seconds, trying to boot, but then would just turn off. The computer would try to restart automatically with the same results until I turned off the PSU switch. I replaced the PSU with a new corsair 430w and the same thing happens. I removed the video card as well and the same thing kept happening. Any ideas? Thanks in advance.
What was your old power supply? Typically the manufacturers include an oem power supply with enough power to run the system. When you added on a GT430, it may have pushed the power supply too hard which led it to fry your motherboard. You should take out your motherboard because sometimes you can notice physical damage. You should see if you can RMA it to HP or have one of your pc knowledgable friend check it.