The 2013 El-Cheapo Power Supply Round-up

Codegen 450X

Unlike Bliss and Powercase, Codegen is a brand which I am reasonably familiar with, but for all the wrong reasons. Most of the Codegen products I’ve come across over the years have been very poor quality, and many were faulty.

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The label makes this out to be yet another dated, 5V-heavy design. The power supply itself is plain grey, and the case isn’t very well ventilated. It’s a little better than the case on the Bliss, but it still only has slots on the front and very small holes on the top.

Load Testing

Test 1 (114.2W Load – Cold)

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Test 2 (194.96W Load – Cold)

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Test 3 (246.55W Load – Cold)

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Test 4 (296.29W Load – Cold)

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The 12V rail stayed within 0.17V, or 1.42% of its nominal value throughout the testing, and dropped by 0.28V, or 2.33%. The 5V rail was always within 0.1V, or 2% of its nominal value, and dropped by 0.07V, or 1.4%. The worst performer was the 3.3V rail, which was getting close to the minimum allowed during test 4, being under by 0.15V, or 4.55%. Its best value was 3.26V, which gives us a difference of 0.11V, or 3.33%. While this result is still a pass, it’s not great. In fact, it’s worse than we’ve seen from both the Bliss and Powercase.

The efficiency was absolutely horrible, with the power supply never managing 80%, in spite of being run on 230V. A similar power supply used in the USA with a lower input voltage would have even worse efficiency than this. The power factor sat around the 0.6 mark, which is typical of products with no PFC. I did attempt to load the power supply to about 350W, but it blew up after around 20 seconds.

Rail	Test 3 (246.55W)	Test 4 (296.29W)
12V
5V
3.3V
−12V
5Vsb

The ripple suppression was actually decent – much better than we had from the Powercase and the Bliss. All of the rails had less than half the maximum allowable ripple at all times.

Disassembly

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The input filtering consists of two X capacitors, a common-mode choke, and two Y capacitors. While there are enough capacitors, there should be another choke. The 450X uses a 4A bridge rectifier, and two 470µF input capacitors from HEC. The switching transistors are Jilin Sino Micro 3DD13009Ks rated at 12A each, one of which just about blew itself in half when I attempted to load the power supply to 350W. On some very well designed and well cooled power supplies, similar switchers can hold up to 450W, but that was not the case here.

The 12V rectifier is a MOSPEC F12C20C, which is a fast recovery rectifier rated at 12A. Considering that the label claims the 12V rail to be capable of up to 16A, a 16A or higher rated rectifier should have been used. It would also have been better to use a Schottky rectifier as opposed to fast recovery, as they offer better efficiency. The 5V rail uses an S30D40C schottky rectifier rated for 30A, and the 3.3V rail uses an S20C45C 20A schottky rectifier. Considering that the label claims 35A and 30A respectively on these rails, these rectifiers are insufficient. The capacitors are all supplied by HEC, and the controller IC is a System General SG6105.

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The fan is made by Dong Guan Xin Yu Electronic Co. It was beginning to fail and would make a loud growl for the first few minutes after being powered on. By the time the power supply exploded, however, the growl had disappeared, and the fan seemed to be pumping out a decent amount of air, so it’s unlikely to have played a major role in the 450X’s failure. Peeling off the sticker and removing the plug revealed that there was only a very small amount of thick grease used to lubricate the bearings, which is clearly insufficient.

Specifications and Conclusions

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Pros: Passable Voltage Regulation, Good Ripple Suppression

Cons: Can’t deliver labelled rating (−2), Low quality capacitors (−2), Low quality fan (−2), Very inefficient (−1), Old 5V-Heavy design (−0.5), Input filtering needs extra coil (−0.5)

Score: 2/10

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