First we will have to start by looking at a few things;
1: What is your cpu temp? Download core temp and prime 95 or intel burn test (intel burn test will get hotter than prime 95 by about 10 degrees). Run a stress test and watch temps, if you are reaching temps of 80+ degrees then i suggest you take it apart and clean all dust between the heatsink and the fan. Also remove the heatsink and clean and apply new thermal paste. Put it back together and watch temps again mine at this point with intel burn test was only hitting 70 degrees but then the fan would kick it up a notch and bring it back down to 67 and stay there. Keep in mind that this laptop has one more fan speed that is reached at about 78-80 degrees. that being said lest move on.
2:Now lets start the overclock shall we? Download setfsb and open it. Click on where it says clock generator and scroll down till you find SLG505YC56DT and click get fsb. Now the bottom slider beside where it says set fsb is the one yo want to adjust. Start by taking it from 90/190 to 95/190 and hit set fsb. This will give a small overclock. From there go up 2 at a time slowly till you reach 100. Once youve reached 100 go up one at a time till your system freezes or blue screens. Remember where you were when it crashed. Restart the computer and repeat this step till you get to just before the point where it crashed and stop. Assuming you on a stock setup with the i3 380m 4gig of ram that is problably 101 or 102. Now go do some stress testing. at this point i was getting about 75-76 degrees on intel burn test which in my opinion is safe considering tj max is 90 degrees.
3: At this point you are overclocked as much as you can go and its problaby at 2.72 ghz, thats 200mhz over stock clock speed. Now for the guys who just want to go farther what i did was went and bought 8 gig of ddr3 kingston ram at 1333 mhz and it allowed me to go farther, up to 2.889 ghz and stable with intel burn test just getting to the point where the fan kicks into high speed at about 80 degrees and then goes back down to about 78and goes back and forth between 78-80 degrees. Keep in mind that in the real world of every day usage you will never hit that high of a temp. Eg if i play the dolphin gamecube emmulator which puts a average of 70 percent load on the cpu playing smash bros melee at 80-100 percent speed i only hit 70 degrees which is more than safe for your laptop considering thats when the fan kicks into a medium speed and its 20 degrees off of tj max!
Note: Some number may vary from laptop to laptop im only showing my results.
If you have any comments or questions dont be scared to post them here. If any mods or admins fell this is in the wrong section or have anything to add or change go ahead and do so.
Take care and happy overclocking
edit: also if you watch in gpu-z you will notice that this also overclocks your inergrated gpu