Dell dimension wont boot after power outage and stops half way through the boot page

The 123 lights on tower translates as:

Routine system activity subsequent to video initialization.
Watch your monitor for on-screen messages.

Disconnect the video cable from the computer and see if you get floating color bars on display. If not, your monitor is defective.

Probably corrupted some importand windows system files.
Boot in safe mode, and do a system restore.

Start, Accesories, System Tools, System Restore..
Choose a restore date. The last one in there will likely do it.
Allow it to do it's thing.. Should be all good. Cross your fingers..

hi

if you CPU has a green light it meance your Power supplay is working fine chack back side of your CPU fan is working or not if it's working then just open case
folow the 2 step

1 remove RAM
2 CIMOS beetery which is on mother board leave your CPU for Some thime re fix both i hope you CPU will give you the disply

Can you check your bios page on startup? Do you see anything on the screen when you first powerup? If you see nothing and only get the flashing lights you may need a power supply.

You may also have a bad HD or perhaps loose memory chips.

You can start by checking the bios for an installed hard drive and memory. If you see those and then it stops booting. Check the power supply.

hi,
If the green lihgt is coming on the board means smps is fine.
there is the issue with the mainboard need to repair.
Thank You.

need to reinstall windows it is corrupted

Most of the time when it beeps, and there is nothing show on the computer screen, it is a RAM problem. A stick of ram may have gone bad. If you have two sticks of ram in the computer, you can try to remove one stick at a time to see which one might have gone bad.

There is no way around this you need to get your OS from Dell and reload.

Sorry.

There are several different solutions for this as posted at this Forum.

http://www.tomshardware.com/forum/51352-2-dell-dimension-8400-wont-boot

1) A lot of people have just removed the Jumper for the CMOS and turned the Power back on and back off and replaced the jumper and/or removed the battery.

2) Several people have reseated the Memory and after booting back up it worked.

3) A few had to replace the Mother Board and CPU but in this instance they had to also replace the Case because the Dell case wasn't really fit for the heat of from the CPU.

4) I had the exact same problem and luckily replacing the Power Supply fixed this for me. I had to cut out the back of the Dell case for the toggle on/off switch but when I tested the old Power Supply it was only getting 5amps and this was causing the Amber/Orange/Yellow light to constantly flash.

I hope this helps!

power supply is probably shot and you are feeding a voltage way over what is needed. I have a dell that refused to operate one day. I went to www dot affordablesurplus dot com and found a 350 watt power supply with all the RIGHT plugs. Never had a problem since.