Modular Power Supplies Less Efficient Say Makers

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If a significant amount of resistance is added, then the fault is with the modular PSU maker for using poor quality connectors. They can make any kind of connector they want, as modular cables will always be brand and possibly model specific.

With RC Cars, which draw quite a bit of current, the default plug for about the past 20 years has been the familiar white translucent Tamiya plug. It worked great at first, but as batteries got better and motors began to draw more and more current, their lack of efficiency became a problem. It was so bad, in fact, that in extreme situations the connector could even melt due to the heat generated by that resistance.

The answer were better plugs. Deans plugs are probably the most popular, but there are many options. The plugs are smaller, provide a better fit, and most importantly have MUCH less resistance. Some will claim that when installed properly, you gain no more resistance than the length of wire they replace. While that may or may not be accurate, the point is modular power supply manufacturers can solve the problem if they want to. The only downside is that it will cost a bit more, but I'll spend a few more bucks to get the benefits of modular connections without a noticeable amount of added resistance.

Admittedly, RC cars only have 2 wires, while motherboards can have up to 24 on a single cable, though the basic wires that will always be in use are never have modular connections. At most there will be 8 wires from any modular cable, which makes very low resistance connections a feasible option.
 
Crap, I think my computer is single handily melting the icecaps. Bragging rights sure have changed. Right after I built my quad core, sli, raid 1, modular psu rig, he builds a sub 300w game machine(including monitor) with a 80+ psu.
 
I call BS on this too. Another connection and a small piece of wire will add a negligible amount of resistance. I doubt you could even pick it up on a multimeter.
 
Tests on this were done by Hardocp.com a couple years ago. I specifically remember reading their measurements, and it does add up. I wont link to it because I'm lazy and just got off vacation, but if you search back, you'll find it.
 
i dont think it's that big a deal. and besides, do you use all of your cables of your modular(even non modular) psu? i dont, so even if it does waste a lil power i only use 2-4 of them. because if i use all of them then go get a non modular one. but then again, as someone here already stated, more expensive(higher capacity) psu's are modular nowadays.

 
Tom's is (maybe was)known for stats. Where are the measurements? How much 'efficiency' can I gain from a non modular PSU. How much does a modular PSU waste? What about different connector types? What about the lost efficiency resulting from reduced airflow due to unused connectors. Efficiency is more than cost also. Man hours are important in that calculation. That doesn't really apply to this article but others I've seen here don't seem to take computer power into account.
Finally I challenage Tom's to always put these green or power efficiency articles in terms of dollars per month saved. I doubt you will. Two cents a month would make the reader wonder why you wrote the article in the first place.
 
I'm calling bullshit, Enermax makes some of the most efficient power supplies, and what are they? Modular!

PCP&C : all single rail? Does that increase the stability and efficiency of a power supply? No, it doesn't.
[citation][nom]haze4peace[/nom]I call BS on this too. Another connection and a small piece of wire will add a negligible amount of resistance. I doubt you could even pick it up on a multimeter.[/citation]
Unless the PSU manufacturer screws it up.
 
Obviously it adds up a resistance as explained by toms, but as how much? since you don't need alot of wires not used up inside your PC i think they too add up to the resistance (the unused wires). Modular and non modular is also another thing that differs a Mac and a PC. Mac proves non modular is much efficient but to an extent that it is not flexible as modular concept. In the end both have pros and cons. Resistance maybe minimized using gold plating like the microphones use that concept.
 
Loses on modular cables exist, but are negligible, few wats tops on most powerfull PSU's. On oposite side, less cables and no need for reductions can make up for this easily as better airflow allow lower temperatures (less power used by components), and no added resistances from connector reductions can make up on modular cables on itself.
 
Damn...what is this, a paid-for article by PCP&C? While there's just enough truth sprinkled about in the blog to make it somewhat believeable, to have only PCP&C as the single quoted "manufacturer", and I use quotes around that because as we all know, PCP&C sources their power supplies from either Seasonic (Silencer line) or Win-Tact (Turbo Cool line.)

But let's examine the statements attributed to PCP&C and contrast them to known testing by an impartial tester.....testing PCP&C states has yet to be done, but has already been done as of 3 years ago by a reviewer most know as JonnyGuru, in an article he did for Motherboards.org in August, 2006.

The entire original testing article is found here...Modular Power Supplies: The Reality of the Resistance:
http://www.motherboards.org/articles/guides/1488_1.html


First, we have this statement:
The voltage drop can be as much as would occur in 2 feet of standard wire.
Click to expand...

So let's see what REAL testing showed.....when applying an 11A +12V load across power supply wiring, fixed vs. modular (a Silverstone hard wired vs. a Corsair modular), the resistance loss was 0.11V for the fixed wire Silverstone vs. 0.19V for the modular Corsair.

Hmmm...a whole 0.08V increase in resistance loss due to the modular plug.

Further, JonnyGuru's testing showed this:

Someone once said that a modular connector's pins have as much resistance as two feet of wire. I can't recall where that came from, but I think our five subjects have shown us that there's actually as much as four times as much voltage lost in a mere 18 inches of cable than there is in a modular connector.

The power supply that showed the most drop in voltage at the modular connector was the Corsair. ....regardless, one has to keep in mind that this drop was only .03V even when there was an 11A load applied to a single connector. That's only a 0.25% drop in voltage during a very exaggerated static load.
Click to expand...

Or the complete 11A testing results:

...under the torture of an 11A load on a single connector the FSP comes out as the king by only exhibiting a .10V drop in voltage.

The Ultra comes out in second, which is strange beause this is a modular power supply. The second of the two fixed cable power supplies actually came out in third over all. This was because of the .02A loss at the connector. Why we're losing this much voltage at the connector on the Silverstone PSU, I'm not sure. But because of this, the ST65ZF was beat out by a modular power supply.

And still, the Antec came in last. But not so much because of loss at the modular connector this time, as the NeoHE only lost .02V at the power supply when the Corsair lost .03, but because of the cable. 0.17V was lost just pushing power through the cable.
Click to expand...


Interesting findings and sort of flies in the face of PCP&C's "we wish there was testing to show what we wanted....." lament.


Then there's this comment:
Worse yet, modular plugs utilize delicate pins that can easily loosen, corrode, and burn, creating the potential for a major system failure. That's why professional system builders specify uninterrupted wire!
Click to expand...


Hello!!! What do you think is at the other end of the wires? Those same "delicate" type connectors....you know, the ones you plug into your motherboard, graphics cards, hard drives, etc. If they're so damned delicate, why are they still used and no one seems to have major problems with them?

JG sums up that FUD with this:

...we still can't ignore some KNOWN ISSUES with modular power supplies that we all need to be mindful of. Any physical connection point, whether you're talking about the modular connector on a power supply or a lug nut on your car's wheel, is a potential point of failure. Connections can work loose. But in some applications they don't work loose once they are in place because, unlike your car's wheel, your power supply is not a moving part.

...people assemble builds with modular power supplies, tie things up all neat and tidy, and then NOT go back to double check the security of the modular connections at the power supply. This can, and DOES, cause HUGE problems. Please double check ALL of your connections whenever you open your case, shove your hands inside and start bumping and yanking on different cables.
Click to expand...


So, testing of modular vs. non-modular power supplies has been done and while there is resistance loss that can be measured from modular connections, as the article and testing by JonnyGuru showed, many times long fixed cable runs with multiple connectors wired into it will lose much more voltage to resistance than a properly designed modular cable.

Strange, I'd think that PCP&C's extra-long cables with multiple end connectors would really end up with worse losses in voltage due to resistance than a good modular focused use cable, like used in most, if not all, modular power supplies.

Again, this blog/article here on Tom's smacks of something like paid advertisement for PCP&C rather than well thought out or researched journalism.....more FUD spreading than pointing out the reality of modular plugs.
 
I prefer modular but looks are a pleasant afterthought. It's a question of airflow and excess cables. I'm always changing around my computers and those cords get in the way. It's just a pain. Every time I have to work on a friends computer I cringe because if I didn't build it, then the case is too small and the cords are always a mess. (I still laugh at my friend because his computer case had carpet sprinkles all over)

My last build I was able to wire with 1 12v cable and one for my graphics card. That's a lot or real estate I saved
 
read it, but never understood the modular psu inefficient crap..
to me it is makers whining to avoid investing in modular PSUs.
my next build will be smaller than mini-itx and i will look for a 300W or less modular PSU.
 
Sounds like the power supply companies got together and made a gentleman's agreement that modular cabling is not only pointless but possibly a detriment. I can guarantee it's more cost savings than anything else. Yes I'm sure it's measureable and continuous lines are better but it's being hyped or rationalized to save manufactures money. How about this... going on their same thought, get rid of the power supply all together and pack it right onto the motherboard.
 
This "article" is poorly written. The tone throughout the whole article sounds like a tabloid rather then something written by a professional. If you're going to make a claim, back it up. Lets see the quotes from Enermax, Corsair, and Seasonic if you're going to include quotes from PCP&C. Gee well look at that, PCP&C is the only manufacturer mentioned in the article that does not have a modular psu. You know it doesn't surprise me that PCP&C would say what they did just to sell their psu's. DUH!! I don't believe for one second Enermax, who's Revolution series psu's are modular, powerful, and VERY efficient would say to go for a wired psu. Same can be said for the other companies.
 
I am becoming more and more convinced Tom's is plugging PC Power & Cooling for them. I first suspected this back when they had interviews with the President of PC Power & Cooling a year or two back and it always seemed that they talked them up compared to every other manufacturer out there. It is a shame to see this site not backing up their articles with facts. If I wanted an advertisement in my research I'd go somewhere else.

It is obvious to most of the readers hear that this article is promoting FUD, and *Quality* Modular Power Supplies are every bit as good as Wired with a minor loss of power from resistance. The benefit of better airflow from less cables more than compensates the extra heat generated from the added resistance.

I have an Antec Truepower 1000W and am only using 2 of the 4 plugs, and I don't have a single empty power connector. This is something I can't get with a non-modular power supply.
 
Modular, Non-Modular it doesn't matter to me. Because I end up using almost all of the modular cables anyway, any "airflow improvements" are null and void.

And are you guys claiming airflow improvements letting the unused wires hang in the open areas of your case? mine are tucked away not impeding any airflow.
 
Measuring resistance with a multimeter can be very misleading for high current applications. To properly measure the resistance of the interface one would have to measure the voltage drop across the connector at the full 40 Amp load then use the well known R=V/I.

As connectors heat up, even slightly, resistance can go up signifacantly. That is why the Fluke dedicated workbench ohm meters are so costly. They have to be able to test at a wide range of currents: 0 to 150 amps.
 
[citation][nom]fletchoid[/nom]Before everyone starts ripping out their modular power supplies, it would be helpful to have some objective testing to determine the actual effect on efficiency of the modular vs standard power supplies. Even then, if the loss of efficiency is minimal, I will stick with modular power supplies. They allow for a much cleaner case, with better air flow, and if a power supply does fail, or you decide to get a more powerful supply, you just unplug the back of the PS, unscrew the PS mounts, put the new one in, and replug the connections. Much easier.[/citation]

Totally agree. I had a modular PSU fail on me a while ago. Instead of unplugging my 6 hard disks, 2 optical drives and a PCIe power connector, i simply unplugged the 4 modular cables, replaced the PSU with a new one and plugged the cables back in.
 
A lot of you are describing collusion between PSU manufacturers. I seriouslly doubt that. They don't care if they build modular PSUs or not. This is marketing and fear. There is a gullible market for green items and they're going to go after it. Ethanol is less efficient than gasoline. That fact doesn't matter to the true believers. True believers also buy computer parts.
The other part is fear. We have a President who is nationalizing industries. Other industries look on with trepidation. They know he has the health care industry in his sights. They know he said he wants to dismantle the coal industry. He is 'Green' so they want to be green also.
 
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