Modern boards use plastic stand-offs to which the board simply snaps into place or is fastened to by ties. Older PC casings use brass ones that need paper or cardboard washers for the task. There may also be an issue with the alignment of the board itself (there was an issue with Gigabyte boards sometime back that had the whole board sagging in one place of the other which prevented the memory modules from seating properly. Use plastic tie-downs where a plastic tie is used to pull the board into alignment to solve this type of problems.



Next, check if the power supply has a switch at the rear if it is on (older models) and see if it works. Check for any foreign metal objects that may be stuck between the board and the case which is shorting it out, again the protection circuit would prevent power up to avoid damage to the various sensitive electronics. A faulty motherboard fan can also be causing the problem so check the fan if it works. You might have also forgotten to connect the power button to the board (along with the reset button) so check that too. A shorted reset switch can also keep the board in a state of permanent off, unplug it to see if that works.

Some motherboards are so sensitive to cooling that no fans connected to the on-board fan connectors would prevent power-up to avoid ruining the processor (this would be the case if you were using externally powered or special/exotic cooling systems) try plugging in a fan or two to see if it works. The worst case is to get the lights and fans working but still there are no beeps, display or other signs of life for it may be a signal of a dead board or power supply.

If your bare systems now functions, you can then add your components one at a time so you can continue to eliminate any problem device. The prices of computer parts have indeed gone down so much that they are affordable to most. If one does not want to spend all the time tinkering and wondering what is wrong then a trip to the computer repair shop would be an easier alternative.

If you by chance got yourself a good deal on a second-hand computer that works just right and is affordable enough o allow you to upgrade some parts then you indeed got a good deal. As you get home, you setup your prize and power-up only to find that the system is locked down by a password. A boot password or worse a system password can prevent access to the contents of the hard drive or the system itself leaving you stranded in the boot-up menu. Don't fret, for there are ways to get around the problem and these work almost all of the time in getting you up and running in no time at all.

First, if you can get hold of nifty utilities from trusted sites of the internet, then that would be easier but it can sometimes corrupt the bios of the system as it forces a program to open the said part of your computer system so be cautious and read all recommendations and instructions in the readme file so you don't cause further problems.

If you're in a hurry and don't have a second computer to do a search, you can always consult the motherboard's manual or simply look at the board for any pins that are labeled BIOS reset/normal. This is a failsafe mechanism which is built in by manufacturers into their boards to allow use of a locked system as yours.