computer not working

My sister switched off the button on the power strip that powers my computer (hp xp) and when she turned the strip back on the computer would not turn on, the screen still was working and the light on the back of the computer was on but blinking off and on. We thought maybe it overheated and blew something so we unplugged it and used the same cords and power cord to plug in our older computer (hp 2000) and that was working and then just turned off suddenly and would not start, but still would power the screen like the first computer.

We thought maybe it was the power cord or the strip so we used a different power cord on both comps, and in different room and they would still not work. Then the screen also stopped working. We think maybe a power surge went through the cord and blew the first one (my hp xp), but also my hp 2000 (which we did not test till 2 days later)? does anyone maybe know what happened?

if so please email me at [email protected]