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Old 12-29-2013, 06:30 PM   #883
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Default Re: the gutless, bloated, and fried power supply hall of shame

Originally Posted by TELVM View Post
The new year's fireworks are eagerly awaited by the masses .

I guess it's my turn to post something...
What I have for you: a Raidmax RX-380K (i.e. a Sun Pro KY-480ATX).



top side (taken a few years back):

another top side (a little more recent - you can see another cap has failed in there just from the PSU sitting in storage):

primary side showing diodes in bridge rectifier and the bent leads on the parts attached to the heat sink:

secondary side shot:

botton side (solder side):

This is probably the crappiest power supply I have around. The case is made out of paper-thin steel. The heat sinks are equally anorexic. Soldering on the bottom side is plain awful. Lots of loose solder balls came out when I first opened it. It's a miracle it didn't short out at the factory. The primary transistors have their leads so bent that they are nearly touching each other! As you can also see from the bottom-side picture, the separation between traces on the primary is very small. I'm pretty sure this thing never passed UL, CE, or any other safety marks. Then again, it's clear from the label the safety marks were forged. The wires are all 20 AWG (with 22 AWG for floppy connector) and completely unlabeled! (not a single safety agency or UL number in sight)

380 watts output??? Yeah right . It may not be very clear from the pictures, but the PCB has some serious "burn-in", and this was not caused by a stuck fan since the fan is spinning fine (although, I should note that the fan was quite dry... looks like it never saw lubrication from the factory). Speaking of which, the fan is a Te Bao Metallic Plastic model M802512M rated for 12V and 0.14A. IIRC, this PSU was powering a mediocre Athlon XP 1600+ system with a GeForce 5200FX video card and 1 HDD, so nothing too heavy.

Primary/input side:
Not much to talk about input filter. We have us two blue (but fake!) Y caps, and a sugar-cane-colored input choke . No X cap. Better than nothing, still.
Moving on... two bigger and two smaller diodes for the bridge. Too lazy to read part numbers, but I'm guessing 3A and 1.5A or 2A diodes. The two bigger diodes are always used, so this PSU should be capable of pulling 300W from the wall with these diodes (of course it won't, as you'll see from the rest of the parts list).
Also on the primary: 2x 200V 330 uF Metacon GK primary caps that read 200 uF and 196 uF on an ESR Micro V4. Primary transistors are a pair of 13007 BJTs in half-bridge configuration. Main transformer is size 33. 5VSB transformer is the standard cute small stuff you always find in all cheap PSUs. Speaking of 5VSB - it's that good old friend, the 2-transistor design . It doesn't have a critical capacitor, though.

Secondary/output side:
12V rail has a 12A 200V fast recovery rectifier. 5V and 3.3V rails share a single 20A 40V schottky . The 3.3V rail is derived from 5V rail in a linear fashion with a CEP51A3 (48A, 30V, N-channel MOSFET).
Output caps:
12V rail: 1x brown CS "LOW ESR" 16V 1000 uF cap placed after a PI coil.
5V rail: 2x JEE "LOW ESR" 10V 1000 uF caps (1x before and 1x after PI coil)
3.3V rail: 1x JEE "LOW ESR" 10V 1000 uF cap after PI coil.
5VSB: not exactly sure. I think 2x CS 16V 470 uF caps originally (1x before and 1x after PI coil), but one of them failed, causing the 5VSB to crazy with anything higher than 50 mA of load. I think I saw the auxiliary rail for the PWM controller (an AZ7500BP) go as high as 30V when this was going on. I recapped the failing CS cap with a questionable STONE 16V 470 uF cap out of a Philips TV that had other STONE caps of the same ratings failed. But it's a crap PSU, so why waste good caps on it? I just wanted to get it working again, which the STONE cap did. 5VSB is good for up to 1.5A of load now, though it does get warm with that load. Before you jump and scream at me... don't worry - I'm not going to put this PSU back in a PC ever again .

Actually, the case from this power supply is now housing the guts of a beefy HiPro HP-P2507F3P 250W PSU that a friend gave me.
Sorry for that wall of text above. Hope you liked this one
Attached Images
File Type: jpg Raidmax RX-380K PSU (1).jpg (162.1 KB, 127 views)
File Type: jpg Raidmax RX-380K PSU (2).jpg (160.3 KB, 140 views)
File Type: jpg Raidmax RX-380K PSU (3).jpg (298.9 KB, 178 views)
File Type: jpg Raidmax RX-380K PSU (7).jpg (310.6 KB, 124 views)
File Type: jpg Raidmax RX-380K PSU (8).jpg (400.4 KB, 120 views)
File Type: jpg Raidmax RX-380K PSU (9).jpg (306.3 KB, 140 views)
File Type: jpg Raidmax RX-380K PSU (10).jpg (291.7 KB, 139 views)
File Type: jpg Raidmax RX-380K PSU (11).jpg (266.7 KB, 149 views)

Last edited by momaka; 12-29-2013 at 07:54 PM..
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