Remove CD's and any floppy disk from your computer. You mentioned no beeps in your description. If there were beeps, then turn off your computer, unplug and replug the mouse and keyboard to the computer, and retry. If there were no beeps, then your BIOS, keyboard, and mouse are OK. However, your memory may be dying or dead. The assumption I have made is that you are running Windows. Windows is trying to boot when you get the the Y's. If it is not your memory, then you have had a virus attack and the master boot record has been compromised. Either way, your repair costs are about the cost of replacement memory. Thanks for reading. We want your business! Saving you money is our service!