Motherboard Repair ASUS P5W DH DELUXE

[krisztian_andre]

Started repairing this motherboard I recently bought broken and one of the components has a burnt hole in it. it's one of the four sot223 like(I didn't recognize the package, it has 3 pins plus a tab measuring 4.6x2.5mm) packages on the picture, it has AE RZ written on it in capital letters and nothing else. Maybe you can help me identify this component from the layout or maybe you can recommend a way to identify if it's an LDO or something else by testing it out of circuit.

[kjs]

that's an SOT89 package from the looks. Can't help you with the rest, sorry.

Edit: the capacitor on the right bottom side looks like the top is buckled up. Unfortunately well out of focus but I would check. If that's the case it is toast.

[krisztian_andre]

The two QFNs that on the photo are marvell 88E8053-NNC1 gigabit ethernet controllers, I suspect the parts in question are associaterd with them. There cans are 25Mhz oscillators if I'm not mistaken.

[bktemp]

Looks like it is beeing part of a voltage regulator (big 1206 cap next to each SOT89).
AE marking gives BCX52: PNP transistor
If it is used as a voltage regulator then the marvell chip is probably also dead.

[krisztian_andre]

The PSU takes 12.5W at standby measured at the line. the sot89s measure between their middle and left and between their middle and right pins in this order: lower left0,3.21  upper left(the popped one)0.54,3.22  lower right0.7,3.18  upper right0.78,3.18   The right marvell chip gets too hot to touch, the left one is slightly warmer than the other chips on the board. The PSU is rated at 10W on 5VSB.

[krisztian_andre]

I desoldered the 4 transistors, no change. Can I desolder a qfn without hot air?