What's up with the MD-500SCPS?

The big draw to the MD-500SCPS we're reviewing today is power, price and modular cables.  500W is a hot number in power supplies.   You'll find that all of the power supplies that we've reviewed during March and into April are between 480W and 600W.  And as with most of Mad Dog's products, price point is paramount, but they do it without sacrificing quality by turning to Super Flower to manufacture their power supplies.  The modular cables sweeten the deal by allowing the user to only add the cables they need, keeping the inside of the case neat and clean and capable of better air-flow.

Mad Dog's power supply uses 2x2 and 2x3 connectors to interface with the power supply. The use of existing connectors allows Mad Dog to keep costs down and since the connectors natively come with clips, there's no problem with cables popping out.  Notice the SATA interface is 6-pin.  This is because the Mad Dog actually provides 3.3V to the SATA drive unlike the other modular power supplies we've reviewed so far.

The cables on the Mad Dog are similar to that of the A.C. Ryan we had just taken a look at, except the heat shrink tubing on the ends actually goes all of the way up to the connector.  The webbing also seems to be a bit sturdier than the A.C. Ryan as well.  The connectors snap into the power supply so they shouldn't come out and there's even a dedicated SATA power connector that provides 3.3V for future SATA drives (currently, SATA drives only use 5V and 12V, but 3.3V is in the specification.)

On the back of the MD-500SCPS we see a little push button and three lights.  When we push the button, the light changes as does the RPM of the fans.  What's nice is that the slowest setting allows the thermostatic control to override the low RPM, so when you start using the PSU and it gets hot, the fans kick up a few revolutions to compensate.  The other two settings are faster and are labeled "normal" and "turbo."  The fans are 80MM in the front, 92MM on the bottom and 60MM in the back.

SuperFlower makes this unit for Mad Dog and I must admit that it is a very clean power supply inside. Unfortunately, the heatsinks are rather small, transformers and AC filtering capacitors are small....  Not quite as bad as Powmax's power supply, but smaller than most of our other power supplies.

It's so "neat" inside the Mad Dog that even the wires for the fans are twisted and then have a clear tube slid over them.

Taking a look inside:

The insides of the MD-500SCPS are very neat.  Unfortunately, the insides are very small.  And it's easy to keep small things neat.  I do like how the wires for the cable interface are routed between the interface card and the power supply housing.  We can see that all three fans are ball-bearing so they should last a long time.

The heatsinks are a bit small than they should be and even with the fans set to "normal" the power supply still got hot after a couple hours of 300W operation.  There's plenty of airflow.  I honestly think the heatsinks need to be a little bigger to help dissipate the heat.

All of the wires, but those needed for the ATX connector and the 2x2 12V connector, route BEHIND the interface card.  We didn't see anything like this in either the Ultra or A.C. Ryan.

Here we can see the back of the interface card.  It looks very clean because, as explained above, all of the cables are routed between the power supply housing and the PCB for the interface card.

Reading the labels and counting the cables.....

So what does the Mad Dog's label look like?

If this power supply can actually perform 45A on the 5V and 30A on the 12V simultaneously, I'll FREAK.  That' would be outstanding.  Unfortunately, judging by the components inside the power supply, I find it unlikely.  In fact, I find it unlikely that this PSU will even do 500W.  Sorry Mad Dog.

Let's take a look at what connectors we get with this power supply.  Keep in mind this unit is modular, so these numbers can change by simply swapping out a cable.

Note the lack of a PCI Express cable.  Also there are no fan only connectors and no AUX connector.  There are plenty of 5.25" Molexes, but only one with the EMI filter, similar to those found on the Raidmax power supply, on it (not to say that the filter on the end of the cable actually makes much difference.)

Results and Conclusion

Ok.  I'll eat my some of my words... I managed to get the PSU up over the label rating of 500W, but there was NO WAY this PSU was going to do 30A on the 12V rail and do anything more than 30A on the 5V rail at the same time.  What I had to do was lower the 12V rail down to 26A.  I then was able to juice up the 5V to 32A and the 3.3V to 4A.  Anything more than 26A on the 12V caused the rail to go WAY out of spec.  Anything more than 505.3W total power caused the overload protection to trip the power supply within an hour.  That's perfectly fine with me.  The PSU pulled off full load without any red numbers.

How I got to full load, in addition to the out of spec 12V rail being out of spec on every test where the 12V load was equal to or greater than the 5V load was very disappointing.  Where am I going to NEED 45A of 5V power in this day and age?  Especially if I can't load the 12V rail equally!

So in features, I give this power supply a 7.5.  If it had active PFC and a PCI Express power connector, it would've scored higher than the A.C. Ryan because the cables that came with the Mad Dog were actually a bit nicer.  Not as nice as the Ultra X-Connect, but nicer.

For performance, I'm going to give this power supply a 7.5.  If you have a computer that loads up heavy on the 5V or won't load the 12V up over 20A while the 5V is also over 20A and you don't want to spend more than $100 on a modular power supply, this might be a good power supply for you.  But if you've got an SLI system... forget it.

This power supply gets an overall rating of 7.5.