Are you talking about the big connector that connects to the motherboard?

You can see the top-left corner of the picture as below:

 

The following pictures are pick up from some other people using the old ATX PSU has TL494 PWM IC inside and he modified it to a adjustable PSU and the voltage up to 13.7V.

 

Haha, great news. I hope it doesn't look like your avatar.

WHAT!!!!
@Lokeycmos, I found this thread from 2011. It may give some ideas http://forum.allaboutcircuits.com/showthread.php?t=58707

 

ok i took it appart. from what it states as a model number on the case, would this be an atx?

 

my power supply isnt the TL494, the numbers on the block are SEC K924A and under that number is KA7500B

 

my power supply isnt the TL494, the numbers on the block are SEC K924A and under that number is KA7500B

Let me have a better look on it tomorrow. But this may interest you meanwhile
http://www.google.com/search?q=KA7500B+atx

 

Here is an example for modified atx psu with TL494 pwm.

The internal structures of KA7500B are similar with the TL494.

Using the VR 15K or 20K to replace the resistor between P.1 and P.7 of TL494, if you want to do maybe you can draw the circuit of KA7500B.

 

The following psu are using KA7500B pwm IC.

http://www.hobbielektronika.hu/forum/getfile.php?id=195169

http://danyk.cz/s_atx01c.png

 

That's a lot of info to take in scottwang! Thanks I checked out the links I couldn't quite follow them tho. It gets real confusing real quick. The link that someone modified it idk how I would do that cuz it's a different power supply. Are the internals rated the same? Confused at the moment Hana going to keep reading over it a. Maybe it will hit me how it's done

 

As I understand the KA7500B and TL494 are compatible. So a description for TL494 should be valid for the 7500B chip also

 

I'm gunna see what I can come up with. I will let you guys know how I made out. But I found what I think is a very good source for diagrams
http://danyk.cz/s_atx_en.html

 

I'm gunna see what I can come up with. I will let you guys know how I made out. But I found what I think is a very good source for diagrams
http://danyk.cz/s_atx_en.html

I saw that website on last september and I already download all the circuits.