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Cheap PSU

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March 11, 2006 3:22:06 PM

I just need a cheap, good quality PSU. Only need like 350W or 400W. Not SLI or xFire. Would like deicated 6 pin pci-e connecter. Never really understood all the numbers on a power supply

More about : cheap psu

March 11, 2006 3:22:37 PM

Oh yeah, I will be overclocking with it too.
March 11, 2006 8:23:53 PM

Would you throw cheap no-name fuel from a no-name vender into a BMW just to save a couple bucks?

You have a nice system that cost some big bucks - do yourself and your system a favor and feed it good clean solid stable power.

This makes good reading.
a c 158 ) Power supply
March 13, 2006 11:50:04 AM

I agree with Conroe on the two FSP PSUs - great choices at a great price.
March 13, 2006 12:52:00 PM

Quote:
I agree with Conroe on the two FSP PSUs - great choices at a great price.
Sorry, but I disagree. Neither FSP models support PFC - mandatory in Europe, likely soon to be in the US. If planning on using that PS for a few years, I would shoot for one with active PFC - it will cost more to begin with, but it will run more effeciently and same operating costs over the long run.

http://www.endpcnoise.com/cgi-bin/e/pfc.html
March 13, 2006 1:23:49 PM

If you value your system and don't want to have to worry about surging, etc, get a quality PSU even if it costs a bit more. It won't pay off up the road if the cheapo PSU fry's your video card or a hard drive.
a c 158 ) Power supply
March 13, 2006 1:26:00 PM

An excerpt from this Dansdata link.
Quote:
But if you're not being billed by power factor - and if you're a home or small business, you're probably not - then an Active PFC PSU, or any other kind of power factor corrected hardware, isn't going to consume any less real power than cheaper gear without PFC. It'll actually probably consume a little bit more, and that little bit more will be noticed by your electricity meter, though the cost per year of this extra is unlikely to be more than you can find down the side of the couch.

If you want to do your part to clean up the mains, then PFC PSUs are a good idea. This might also qualify as enlightened self-interest, because the rate that domestic power consumers are charged per kilowatt-hour is no doubt influenced by their overall power factor. Everyone who swaps out low-power-factor gear for PFC gear lightens the load on the grid, and this may delay power price rises (or, if you live in Happy Land, actually cause the price per kilowatt-hour to drop).

Active PFC PSUs may also deal with lousy mains power better than passive PFC units, but PC PSUs generally handle spikes and surges and dropouts pretty well already, and a proper outboard power conditioner is a better solution to that problem, anyway.

So by all means, buy an Active-PFC-equipped PSU if you like; they do no harm, and they're generally high quality in other respects as well. But don't think that PFC of any kind is going to save you any money, if you're using ordinary domestic power.


The whole article is interesting and debunks the myth that active/passive PFC is a necessary feature for the consumer. The money would be better spent on a good UPS - not power strip - to get clean power.

The point on PFC being required in the USA is interesting. Do you have any more details or links on that topic?
March 13, 2006 1:31:04 PM

I have both a FSP-450 and a Antec True Power 430. The Antec cost twice as much, but has much larger caps. Both do what thay say they will. With a good UPS, the fsp is fine.
March 13, 2006 10:11:11 PM

Quote:
An excerpt from this Dansdata link.
But if you're not being billed by power factor - and if you're a home or small business, you're probably not - then an Active PFC PSU, or any other kind of power factor corrected hardware, isn't going to consume any less real power than cheaper gear without PFC. It'll actually probably consume a little bit more, and that little bit more will be noticed by your electricity meter, though the cost per year of this extra is unlikely to be more than you can find down the side of the couch.

If you want to do your part to clean up the mains, then PFC PSUs are a good idea. This might also qualify as enlightened self-interest, because the rate that domestic power consumers are charged per kilowatt-hour is no doubt influenced by their overall power factor. Everyone who swaps out low-power-factor gear for PFC gear lightens the load on the grid, and this may delay power price rises (or, if you live in Happy Land, actually cause the price per kilowatt-hour to drop).

Active PFC PSUs may also deal with lousy mains power better than passive PFC units, but PC PSUs generally handle spikes and surges and dropouts pretty well already, and a proper outboard power conditioner is a better solution to that problem, anyway.

So by all means, buy an Active-PFC-equipped PSU if you like; they do no harm, and they're generally high quality in other respects as well. But don't think that PFC of any kind is going to save you any money, if you're using ordinary domestic power.


The whole article is interesting and debunks the myth that active/passive PFC is a necessary feature for the consumer. The money would be better spent on a good UPS - not power strip - to get clean power.

The point on PFC being required in the USA is interesting. Do you have any more details or links on that topic?The problem with this arguement is it attempts to debunk a non-issue - whether someone needs it or not, It is here, the EU demands it - the world economy being what it is means that makers will prefer to make one type rather than two. I also note there are several articles on both sides but most that I have seen tend to support PFC, or at least accept it as inevitable.

I may be off on the saving money over the long run, but I don't think so - but perhaps that is just because active PFC generally comes with the better (more efficient) PSUs to begin with - however, there are some inexpensive PFC PSUs out there.

I also note that every time the refridgerator, oven, air conditioner, toaster, hair dryer, or other high wattage appliance cycles on, sags, surges and spikes occure. Who knows what is going on with the power in apartment complexes. Many houses have old wiring that is rarely inspected. A PS that is better able to deal with anomalies is a good thing.

My main point still stands, why feed your $2000 PC power from a $40 PSU? Is saving a few bucks here the right place to cut corners? I don't think so.

I said "likely" soon for the US - meaning 3 - 5 years - I will try to find where I read that.
March 14, 2006 1:39:05 AM

I would say go check out the Antec SmartPower 400W before you buy, or even better a TruePower
March 14, 2006 1:55:55 AM

thermaltake 430w like 45 bucks
March 14, 2006 1:58:00 AM

after all my bad experiences with every thermaltake psu i've ever bought i wouldn't go near those
March 14, 2006 2:05:34 AM

A Cooler Master Real Power 350 came with my Cavlair case (I replaced it with the Antc True Power 430.) But I had it around and built another system and used it. With a Radeon 9600 I can overclock that 530j to over 4ghz. I have had it like that for some time now and it's still going strong. It has suprised the heck out of me. That PSU has one 18a 12v rail, the FSP 450 has two.
March 14, 2006 3:40:25 AM

@Rugger - I have not been able to find where PFC may be required in the US (still looking but I note several jurisdictions, in addition to the EU, are looking into it) - but I have found several documents which seem to counter the Dansdata remarks about efficiency - and therefore long term cost. I note that it is true that adding active PFC reduces input effeciency - but just slapping a PFC circuit is not enough as shown in this PowerElectronics article.

This Lambda article shows how, with PFC a power supply's efficiency can be increased significantly. A more efficient PS can only lead to lower energy bills, it works less so produces less heat, which in turn, causes less heat related stress and aging on the PS internal components. Lower heat also means quieter (or silent) operation as less powerful, fewer, or even no fans may be needed.

For those still uncertain about what PFC is, Wikipedia has a good write up on it.
March 14, 2006 4:20:45 AM

http://www.hardforum.com/showthread.php?t=1000883
Best PSU thread.
Quote:

PFC: Power Factor Correction: This has always been important for large scale commerical applications, now it is something that the home & small office user can also consider,
especially if you are going to be operating outside of north america. Here is a good explination of PFC: http://www.rojakpot.com/showarticle.aspx?artno=81&pgno=...
APC on PFC: ftp://www.apcmedia.com/salestools/SADE-5TNQYL_R0_EN.pdf


Thanks Rugger, I fixed the link. I will tell David. :D 
a c 158 ) Power supply
March 14, 2006 12:25:44 PM

Thanks for the link!

The Rojakpot link was broken. Here is the updated updated link.

@Bill: I believe you're misinterpreting the Lambda article. Based on my interpretation, PFC does not inherently increase the efficiency of the PSU - it reduces harmonics in external lines and can increase output power of the PSU. I agree with the harmonics statement, but I think the statement on increasing output power is suspect. If a PSU is rated at a certain output, then that is the rating - PFC or no PFC. The PowerElectronics article is interesting in its approach/premise that PSU architecture itself needs to be redesigned. Basically, integrating PFC into design architecture allows improvements/efficiencies in the PSU to increase the PSUs efficiency and reduce line harmonics. But it doesn't say that PFC itself increases efficiency - it will allow other improvements in the PSU to increase efficiency.

I will agree that PFC is typically used in higher end PSUs that have higher efficiencies. I will also say that PFC will probably become the norm for PC PSUs, but I still don't agree that it should be a deciding factor in purchase of a PSU today. We'll have to agree to disagree on that... :wink:

On your statement about feeding a $2k PC with a $40 PSU. I completely agree that you should have a good quality PSU for any modern PC, but I don't agree that the PSU needs to be expensive or have PFC to be good.
March 14, 2006 3:50:45 PM

Some of these other supplies mentioned here are okay, but I've had even Antec supplies crap out on me before their time. It's tempting to de-emphasize the power supply because it's not a glamorous part of the computer, but it is an integral part of the 'foundation' of your system. You want a rock solid supply that's going to feed your mobo clean, consistent juice. For my money PC Power and Cooling supplies are tops. They're made right here in the US. They have great specs, great heat sinking etc.. I've never put anything less in a system that I value and rely on. True, they don't yet have all the features like detachable cabling, but that's what cable ties are for. The bottom line is that they're solid performers and if that's important to you in a power supply they're worth checking out.

Think of the power supply not just as another component in your system but as an investment in ensuring the components of your system run smooth. Don't mean to sound like an advertisement, just my experience. Good luck
March 14, 2006 4:52:01 PM

Quote:
Based on my interpretation, PFC does not inherently increase the efficiency of the PSU - it reduces harmonics in external lines and can increase output power of the PSU.
Exactly! It increases output power of the PSU - wasting less energy, some in the form of heat.
Quote:
If a PSU is rated at a certain output, then that is the rating - PFC or no PFC.
I agree, a 500W PS is a 500W PS.

And so if less energy is being flushed out the back, and 500W is 500W, there must be some energy savings somewhere. Whether that savings justifies the extra costs or not, is up to your own situation.

My thoughts are as long as I can expect ATX form factor to be the standard for a while (I don't see BTX taking over any time soon) I am going to install PSUs that I can expect to carry that PC through a couple motherboard/CPU upgrades during the next few years, or an extra drive (RAID?), video card, or even a new case - even if I don't think now that I would ever want that.

For sure we all agree on getting a "quality" power supply - regardless if it has PFC or not. Quality does not necessarily translate to features - and that's okay - quality PSUs use tighter tolerance components with longer MTBF rates, and can generally take abuse better. This translates to me to mean 18 months from now, chances are good my 500W supply is still putting out 500W of good, clean, stable power.
March 14, 2006 5:19:06 PM

Despite TT's flaws, I've got a non-PFC 480W Silent PurePower that works great. Take a look at my specs, in addition to 2 HDD's, 2 CD-Drives, 2 120mm and 2 90mm fans, and I've got pretty good volts @ idle (I Forgot to start recording on ASUS Probe so I don't have load volts yet):

5V: 4.972V-4.99V
3.3V: 3.376V-3.392V
12V: 12.544V
a c 158 ) Power supply
March 14, 2006 6:11:38 PM

Quote:
Exactly! It increases output power of the PSU - wasting less energy, some in the form of heat.


When you said this it made me rethink my statement and more thoroughly read the Lambda article. I think the 2 most important paras are "Reducing Line Harmonics" and "Summary." A closer look at that article leads me to these conclusions:

1. A PFC PSU reduces line harmonics losses on the power supply line that feeds your PCs PSU - the power company's line, your house circuit breakers and the wall outlet. The power losses are saved on the power supply lines - not in the PSU.

2. Because a PFC PSU reduces losses on the power line, that power line can supply more usable power. The "additional output power" is on the power supply lines - not the PSU - and are result of less losses from line harmonics.

In the end we come back to what PFC actually accomplishes: active or passive PFC reduces line harmonics on the power supply lines that feed your PC. Is PFC a bad thing - hell no! PFC PSUs will likely become a rqmt in the near future. It reduces wasted power on the lines that feed our homes and businesses. That reduction in losses means that less fuel will have to be burned to supply our power. BUT PFC provides no direct benefit to the consumer in the form of increased efficiency or the resultant money savings.

BTW Master Sergeant - Thank you for your service! :cool: :wink:
March 14, 2006 6:19:42 PM

Quote:
Despite TT's flaws, I've got a non-PFC 480W Silent PurePower that works great.
None of the big names are without criticisms - even Antecs, a long time favorite, had problems revealed in Tom's PSU Stress Test. I have not found the failure rate of TT supplies to be any worse than the other big names - and the TT Silents Pure Powers can be very quiet.
March 14, 2006 7:19:36 PM

Added: Missed your reply Ruggar, thanks!

I understand what you mean with PFC and that makes sense, and I agree with you, in the technical sense.

In my absolute refusal to totally back down, in a subtle attempt to save some face :lol: , I will beg to suggest:
Quote:
PFC provides no direct benefit to the consumer in the form of increased efficiency or the resultant money savings.
... may not be the point either. No direct benefit, as in a user will see no change in his monthly electric bill - yes, I accept that as true.

But, when multiplied by the 10s of millions of home PCs in the US alone, that impacts entire grids - and when demand on the whole grid reaches capacity, many things may happen, including rolling blackouts (not uncommon events in California), brownouts, and other overload situations - resulting in lost production - maybe even electrical damage to to equipment in extreme cases. Power companies have to step up production (consuming more fuel), or buy electricity from somewhere else on the grid (at higher costs) - all those costs are passed on to the consumer. Industries are consumers, their higher energy costs will be passed on to the consumer too.

I have 6 PCs in my house now - many homes have 2 or more. It adds up.
a c 158 ) Power supply
March 15, 2006 1:17:25 PM

Quote:
In my absolute refusal to totally back down, in a subtle attempt to save some face

:lol:  :cool: :wink:
Quote:
Power companies have to step up production (consuming more fuel), or buy electricity from somewhere else on the grid (at higher costs) - all those costs are passed on to the consumer. Industries are consumers, their higher energy costs will be passed on to the consumer too.

I definitely agree on this point and that PFC is not a bad thing for the consumer....as long as the consumer isn't overcharged for it as a feature. Unfortunately, as PSU mfrs try to separate themselves and their products from their competitors. A lot of mfrs have started using PFC to differentiate their products and some are misleading their customers. I'll end with this: PFC will become mandatory and will benefit the consumer in the long run.
March 15, 2006 7:02:07 PM

Quote:
I'll end with this: PFC will become mandatory and will benefit the consumer in the long run.
Agreed.
!