Acer computer t180 boot up problem
First, remove all the peripherals and addiotnal hardware attached to the computer except the mouse, keyboard and the monitor and try booting the PC to the Safe Mode.
You can press and hold the F8 key after the Acer logo when the PC boots to access Safe Mode.
If you are able to boot to Safe Mode you can perform a System Restore to see if it resolves the issue.
To perform System Restore:
Click the Start button, click All Programs, click Accessories, click System Tools, and then click System Restore
If the issue still persists, you can open the computer case if you are comfortable with that. After that we need to clear the CMOS Battery and try accessing the BIOS.
Final resolution would be a One Button Recovery. It will delete all the data from the C drive of the computer. So, you may have to backup the data from the hard drive connecting it another working computer if you don't have a backup with you.
You can also use the Recovery CDs to perform a Recovery, if you have created them.
Hope this works!