5 Volt put through a 3 volt circuit

[burnt01]

I have been doing some work on and Playstation 3, but it may as well be a pc motherboard. I wanted to flash a new imagine to its nand so to do that I hand to solder wire directly to the nand chip's legs and also supply the board with 3.3volts

To supply the board I used an atx pc power supply and tested the output and it was indeed 3.3volts. During my first flashing attempt I thought I herd an arcing sound very faintly for about a second, but i just thought my mind was playing tricks on me.

the flash was a success but there were 2 chips to do so i connected up the second nand.

The second nand couldnt be detected so i checked my wiring and found my 3 Volt line to be 5Volt and climbing so I quickly switched off. Turns out my power supply had failed and after taking it apart found a broken/burnt trace to be the culprit. Nervous I began to flash again and it turned out to be successful.

I put the playstantion back together but it would not boot up. after checking the resistance from the 3.3volt circuit and ground is now 66ohms and it used to be 390ohms.

My question is, what could have gone wrong? The nand's legs are fine and not shorted, the circuit has little of no protection, only things connected and the major chips i.e. CPU, GPU, Southbridge, ram, Sata ect with only caps to ground for power smoothing.

could one of the caps be at fault? or is it more likely to be the chips?

[pebe]

Most likely you have damaged a chip. They don't like excess voltage.