A Word About Power Supplies

OKIA Power Supply

This story all started with an eBay purchase, consisting of an eMachines personal computer. A customer of mine lost their computer when a severe power disturbance took place, and the resulting power supply failure also killed the motherboard.

They wanted to try a direct replacement first, so I found and purchased what seemed like the perfect thing--an exact replacement system from what seemed like a reputable seller. It even arrived well packaged, so I was surprised when it did not work.

I was a little less surprised when I saw that the original Bestec power supply was gone, replaced by a 450 watt "OKIA" power supply. Clearly something had gone wrong, although the reason behind the replacement was unclear, especially since the seller billed the system as working. I later discovered the motherboard was not the same as the customer's system...the original had an Intel 845 board while the eBay system had an Intel 865.

So I'm not sure what happened. I suspect the original 845 board in the eBay system died when its power supply failed. If there was a replacement board, it is hard to say how it failed.

What that left me with was a perfectly serviceable case and seemingly good power supply that spent a few months sitting around doing nothing. I found a deeply discounted triple core AMD Phenom CPU and an Asus motherboard, and they went into this case. Everything seemed to work fine, but one day I needed a working ATX power supply to test another system. Since this system wasn't in use, I borrowed the power supply from it.

I was astounded by how little the "450 watt" power supply weighed. It seemed to weigh almost nothing. Time to break out the screwdrivers to see what's inside:

What's inside an OKIA Power Supply

My first reaction: "450 what?" Milliamperes, perhaps?

That this supply has a four hundred and fifty watt rating is...uhhh...well, it's "interesting". It almost certainly won't stay together long enough to meet that rating.

Well, it might meet that rating for a very short period of time. It's not going to be long enough to matter, however, and it may damage something else in the computer when it does blow up.

Alongside the thin heatsinks, you might also notice the number of empty component spaces on the PCB. Most of these components would be line filters, power factor correction circuits, and other parts that aren't strictly necessary but are found on higher quality power supplies. There is no active fan control, only a fixed voltage output for the cooling fan. Amazingly, the cooling fan does run at a respectable speed, something that is a bit uncommon with many power supplies that move just enough air to barely keep their internals running at safe temperatures.

If you looked closely at the picture (no, I didn't notice it at first either), you will see that there is heat-related discoloration around one of the smaller transformers.

There is no way in the world this power supply will ever achieve the ratings printed on the nameplate. In fact, looking at it and taking an educated guess, I would say it is good for about 150-200 watts at best.

It may not even be good for that much power output. I found a nearby dead Bestec power supply and opened it up for cross comparison purposes. Now, Bestec power supplies are widely regarded as being of poor quality, and as I mentioned above, when they die, they have been known to take other system components with them. The Bestec power supply I took apart claimed to have a 218 watt output rating.

Bestec PSU Internals

That's quite a difference, isn't it?

Right away, you will notice that the Bestec power supply is exceptionally well built by comparison to the OKIA. Even with Bestec's reputation (which may not be entirely justified, because I've got a lot of computers using their supplies and have never lost a single one), this is a respectable-looking power supply. While it may still be a lightweight for today's modern computers, this supply most likely can meet its rated output, at least for a little while. You will notice that the heatsinks and transformers are larger as well.

Bestec also put more ventilation holes in the case, although the fan in any working Bestec supply doesn't move as much air as that in the OKIA. (The fast moving fan in the OKIA supply will probably keep it from going bang a little later than it normally would have under heavy load.)

Let's do one more comparison.

OKIA PSU Weight Bestec PSU Weight

(rather amazingly, I was able to find my digital scale--although it does appear to need a new battery!)

What you can see is that the smaller Bestec power supply weighs a little less than twice as much as the OKIA. The OKIA weighs 1 pound and 13.4 ounces, while the Bestec clocks in at 2 pounds and 15.6 ounces.

The OKIA power supply appears to be a product of Broadway Com Corp, although I am not sure if they merely resell or actually have an active role in producing OKIA products. Various resellers--including Newegg.com--do carry them, and they are--as I expected--priced very cheaply.

I tried hard not to make this comment, but I wonder if you or your PC hardware will really end up going to "1134" if you use an OKIA power supply. Sorry, yeah, it's a bad joke.

I would strongly recommend you look elsewhere for a power supply. In the world of power supplies, you definitely get what you pay for. A good quality power supply should have certain qualities to it--including weight (no reasonably capable computer power supply should be a feather light object), plenty of places for air to circulate, a good quality fan and plenty of power connections. And if you get a chance to look at the internals, you should see good quality construction with large enough heatsinks and components to handle the load. You should also see plenty of filter circuitry.

But if nothing else, there are some good power supply brands to look for. I strongly recommend buying the best power supply you can afford, and I would recommend any of the following choices:
You will be glad you spent the extra money when it comes down to the wire and your power supply is tested to its limits or damaged when (not if) a power or internal fault takes place.
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