Overclocking problems.. No video now

[Dbivian]

So I decided to try and OC my CPU and Ram last night and .... well, it didn't work. I changed the voltage a few times and it kept coming up on a error screen. I used my MOBO Bios M.I.T. to overclock. It allowed me to go back into the BIOS and I thought I changed everything back to normal, but now I get no video. I did not "return to default" my settings, I did them individually.

When I hit the power button, I see all my fans and led's light up, but there is no video. I have tried the following things already:
-Remove video card and run onboard video
-Reset CMOS by taking out the battery on MOBO
-Removed 1 of my RAM modules

At first I had no power to my keyboard, but now my keyboard remained lit up even after I powered down the rig (after CMOS reset). I need some suggestions. I definitely think its a PSU/voltage issue, but I cant even pull up the bios to default everything...

INFO:
Gigabyte MOBO GA-MA7856G-UD3H
AMD Athlon2 X4 620
Rocket Fish 550w PSU
ATI HD 4870 GPU
2-2Gb G.Skill OC Ram

 

[W Craven]

-Reset CMOS by taking out the battery on MOBO


You also have to put a jumper on the cmos pins and wait about 5mins..

or if it's like my Gigabyte board>>> power down and switch the rocker button on the power supply to off and then hit your front power switch and hold it in to discharged the stored power.. let it set for about 15mins without any power and it will reset the bios on it's own.

 

[Gingerbread]

I can't get you correct but if it is the problem where your computer seems to start but there is no picture (no signal) on the monitor, well it has happened to me, but anyways I doubt your problem will be fixed like this but still I think it's worth trying. Personally for me - I unplug my power cable and then plug it in again. It works on the 2nd or 3rd time though. I still haven't bothered to see why this happens.

 

[Dbivian]

Problem solved. I had to do the following (some may have been overkill) in order to get my computer working again:

-Remove the graphics card
-Unplug DVD-Rom drive
-Unplug HD
-Remove 1 of my RAM modules

This allowed me to run just the BIOS off my onboard graphics and reset my BIOS to default. Then I put everything back in and I'm in business!