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[iceman4208]

looking at the power supply in detail,  there is a diode that looks it blew up in the very center of the power suppply, does that make sense?

[christineyoung]

If a did blew coudl expalin why no power elsewhere.

My main concern is what caused it.  Look at motherboard closely for incorrect solder points, solder bridges, solder spills etc.

What is the overlay layers marking for blown part? ( if diode woudl be D???, if capacitor will be C?, if resistor will be R??? )

[cravavr3]

if you look at that metak thing where Q1 is listed is the burn mark beside/close to the metal thing?

As q1 represent ths black thingy above with 3 pins coming down to motherboard

if its close to the metal thing its resistor r13

[cravavr3]

D55 and D56 are same diodes

[iceman4208]

you are right it is R13, i can barely make out the label.  It is so burnt it looked like the diode beside it.  ok, R13 blew so bad, you can see were it bit into the prongs of the transistor right next to it.  Any ideas?

[cravavr3]

on my cheap volmeter, hard to get accurate connection.

setting - reading
2000 - 0.33
20k - 0.03
200 - 32.8

are readings of R13

[iceman4208]

so you think it will work if i put a 33 ohm resistor back in R13?  Can you see the color bands on the resistor?  they'll give you the accurate resistance of the resistor?

[cravavr3]

As you know its in awkward area, and hard to make out bands.

But looks like orange, orange, ( black or brown )<- I beleive more black

Use my readings above to verify resistance read.

[iceman4208]

Yea, it is a 33 Ohm, i was able to take it out and it stilll gave a 33 ohm resistance.  I'm starting to wonder what popped and left the black marks right there.  The 3 pronged piece (i guess it is a transistor) is my only next guess.

thanks for your help,  

I think I am just going to buy a new power supply, its only 25 bucks.

[cravavr3]

Hmmm... all i see is R13 and D5 on other side of the metal thing.

SO you have burn mark in thsi general arae on PCB.

what about r26 is it present

[iceman4208]

yes, it is present.   Here is a pic of power supply, you can see the black mark under the 2 left prongs, I have removed R13 and the fuse

[cravavr3]

Looking at the image and knwoing all parts are present in general area, i would assume something as left in unit ( lost screw, ect ) or a bug was present and shorted the two legs.

But since you cannot power up and get voltage the transistor may be damaged.

Readings on mine are K2843.