So the processes will vary, but what could happen...

KUL airport security.... They *MAY* ask you to pull out your laptop and turn it on/perform a task (VERY unlikely but it does happen). You may want to make sure your laptop is fully charged and powered off before getting to the airport (just so you don't have to plug into a wall) This may also happen at NRT and/or BOS (highly unlikely but be prepared)

KUL at the gate... They may ask you to gatecheck the bag with your laptop. Most people I know usually tell them there is a laptop in the bag with a lithium battery that can't go into the hold (and there are other various other precious items in there). Usually not an issue, but just in case.

In-flight... For most gaming laptops, you're mostly on your own to power it. Most airplanes can go up to 90w before it becomes hit or miss to powering your rig. Often the issue is when you plug the brick into the plug (couple of reasons including the socket doesn't hold your plug properly or the power drain of the brick when it first goes in). If you dig around in this sub, you'll find the relevant threads for how people resolved their issue.

Other than that, you should be good.

Actually, one other thing... I can't speak for the Malaysian government, but you might want to take proof of ownership (like a copy of the receipt) with you. Two reasons.... 1, so you can get servicing in BOS if there is a need. 2... On the way back if the immigration staff accuse you of buying the laptop in the US and then bringing it back here (again, unlikely, but better prepared than not).

May sound tedious but better be ready for it than not and possibly have some bad consequences.