At first PC wouldn't turn on and after disconnecting everything from the motherboard and putting it back together it turned on and now it won't get past first BIOS screen. Keyboard and mouse which are USB also aren't working and I can't get into BIOS. Please, help!

Any error messages on the boot screen?

do you know enoough about computers to check to see if your hard drive is not being detected?

If not here is a Google Search for you ( and not one of those meme ones )

Nothing, just the BIOS screen saying press Del to enter Setup or F12 to enter Boot menu but I can't press anything because the keyboard doesn't work and I'm not able to get a PS/2 keyboard at the moment.

@Dagbiker Well, I haven't tried it but I can google it and then try.

Are you hooking the mouse and keyboard to the back USB ports? If you're plugging them into the front, you may have unplugged those jumpers from the mobo too.

Could be a number of things.

Do you have the mobo speaker installed? If it's installed and it's not making any noise then ok.

Your cmos battery might be dead and that could've disabled the usb legacy support in system boot.

-The mouse and keyboard are hooked in at the back because I don't have any front ports and that probably isn't the problem.

-The PC isn't making any beeps but I think the HDD has suddenly gone bad. I unhooked the IDE cable and the power cable and hooked them back in and started the PC and it got past the first BIOS screen but then it said: Verifying DMI Pool Data... Can't find system drive. Insert System drive and press Enter. I tried to press Enter but I did nothing and then I shut down the PC and pressed the cables more firmly into the HDD and then it was back to the problem described in the first post.

Found the problem. One of my memory modules failed and I took it out by accident and now it is working perfectly.

Thanks for the support!