Please help me (overclocking)

[Deadpixel]

Ok so My XP crashed on me so I never turned on the computer went to do something else.

I turn it on (I am dual booting Vista and XP) and I get the BIOS POST message.

It freezes, so I restart.

Get the POST message again and it says "cmos checksum-error" everything is set to stock speeds.

I think thats fine, and when I continue, it just sits at a black screen .

Asus P5NSLI & Core 2 Duo E6420 only overclocked to 2.27GHz

Please help.

 

[Deadpixel]

Ok so I unplugged cpu fan, took out the memory, unplugged the hard drives, and plugged everything back in.

And now its just this beeping noise and its continous.

Please help me.

 

[Deadpixel]

Ok took out the battery got into BIOS, but it seems like I will need to do a reinstalltion of Vista and XP, because after the BIOS I just get this black screen /

Do I need to reinstall?

I tried inserting my vista disc, and once its in, I get the same black screen.

Please help