I came up with a way to keep my power supply cool.
I have an m17xr3M17xR3 Alienware laptop which power supply gets extremely hot, especially with overclocking. It's just drawing more power from the supply than it used to. Now that I have unlocked the BIOS and am pushing the CPU and GPU harder, which in turn draws more power the CPU, has gone from stock 2.4GHz up to 3.7GHz, which it seems to have no problems.
Doing very stable temperatures, no real increase from stock, I did adjust fan timing so they come on earlier now, but overall temperature never exceeds 80 degrees Celsius. The main issue was the power supply getting so hot you couldn't touch it.
I solved this by cutting a rectangular wholehole in the top of the plastic on my PSU and attaching 2 old CPU heat sinks with the fans still attached to the metal plate. Inside the PSU, some heatsink thermal paste and an old 12V power adapter to power the fans.
It never gets above 20 degrees Celsius now.
Here is a pic: