It will not power up when we push the on button on the tower?

try this; carefully detach (pull off) the front panel of the base tower unit.. and behind the plastic front that you just took off there's a little button that you can push to power off and on. The power button just goes through the plastic cover and pushes the button.

Either the power supply or front panel switch is bad. Try another push switch first. Power supplies are common to fail on these.
Thanks

make sure the outlet is recieving power

unplug the tower from the outlet & then replug it in & see what happens

make sure all cords are plugged in correctly in the back of the tower

then if nothing happens after you push the start button, power supply & cord could be bad

the same thing happened to my daughter's pc & had to replace power supply & shorted out the motherboard

check the bezel/power button
try to open the tower but you have to make sure that its unplugged/ after unplugging the power cable press the power button for about 5 secs to drain the flea power then check the power button maybe its broken or the cable connected to the power button to the main board is damaged or loose.

power off and disconnect everything....wait 10 minutes....reconnect everything....push in and hold tower power button....while holding button turn power supply on.....continue to hold for 10 seconds.....let go of power button....restart...

Have you connected power cable to rear of Tower? Turn on power plug
and all connections are in place.

Front of Tower, look for a push button, may not be to obvious, there is one, just a matter to locate

the monitor is in power saving mode not the tower check your connections to the monitor and the tower

Check id main board is getting power of not , You need to open tower and check if processor fan is stuck , Open RAM module and clean the slots , Check all power cables , Before unplugging th power cables make sure there is no electricity pass on tower , post reply for any clarification

Well unfortunately you cant get one to buy for any case or tower, what you will need to do is get your self a new case(tower) or simply find an old case and take one out from it..