Hi, After trying to upgrade my RAM my computer does nothing. When I first inserted the 2 bars he gave 1 long beep. So I removed the new bar, and just inserted my old back in. Now my bootscreen was all scrambled up so I couldn't see what he was doing. I've decided to clear my CMOS. When I started the computer, something was burning .. I instantly cut down the power, checked everything, but there was nothing damaged at first sight. CPU looks fine too. Now when i start my computer the only thing that runs are my fans. What can be the cause ?

By the time the smoke gets out the damage is already done. Troubleshooting has been described here hundreds of times if you care to do some reading of previous posts on the forum. After you've done so and followed some of the suggested testing procedures then post back outlining the steps you have taken, unless of course you determine which and how many of Powersupply, CPU,RAM,Graphics, Motherboard, Heatsink fan or peripheral components were fried. I used to have a signature but it disappeared and I just couldn't be bothered writing another so please feel free to ingore this.

Tried to troubleshoot. I only don't have a multimeter, so I can't check for the voltage.. I've removed all the components like videocard, soundcard, harddrive, .. still no post message. When I add the soundcard, its fan works, all the leds work too .. I guess the only thing that could be broke is the mb or the cpu .. am I right ?

I also can't shut down my computer by holding the powerbutton for a few seconds .. i really have to cut down the power..

I suspect you shorted the MOBO near your memory slots or cracked it inserting/removing memory. I suggest you try another MOBO.