Need help reducing 12v dc to 8.7v dc

[Modme]

I'm kinda a newbie to electronics at least this aspect I do modifications for game consoles and got bored with that and decided to take it a little farther. My last project was such a great success that I wanted to see if there was room for improvement. I have 2 power sources and i want to reduce it to just the one, one it is an ATX power supply which I use 5v and 12v from the other is a 8.7v power adapter(from a playstation 2) so basically I want to eliminate the power adapter and stick with just the ATX power supply. Can someone point me in the right direction or help me with this Thankyou

 

[MrDEB]

depending on current needed

but simple method would be to use a 7809 voltage regulator and a diode.
get you about 8.5 from the 9v
or a zenier diode
or use an adjustable voltage regulator
there are numerous power supply circuits on the web some using adjustable voltage regulators.

 

[sheldonstv]

lm317 adjustable reg would do....