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Computer Won't turn on


spacesurfer

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Well I tried, it seems that you 2 (spacesurfer and Tripredacus) are blind to see the difference between a cheap a** 400W PSU (17-19A on ONE 12V line) and a real 380W PSU (TWO times 17A (Lets say 30A combined?) (TWO 12V lines)).

Dig out your pocket and go for a "future proof" PSU: SeaSonic S12 Energy Plus SS-650HT.

That should do the trick :).

Dude, I've built only 3 systems so far and never considered the PSU as a vital component with certain specs to look for. Hence, don't know much about them except the wattage. Would be delighted for education. Anyway, so you are saying that the 380W Antec delivers more than just the 380W as claimed???

The physical lesson in high school on W, Amps, and volts isn't coming back to me.

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The physical lesson in high school on W, Amps, and volts isn't coming back to me.
Okay, no problem, let´s go back to the PSU you picked:

The specs look "ok" with:

Output +3.3V@32A,+5V@50A,+12V@24A,-12V@1.0A,+5VSB@2.0A

The +12V is market in red, and the +5V in blue for easy reference.

The 5V+ line is heavily overdone with its 50A, not needed at all, only for a part of the motherboard and some other low level I/O, not even getting close to those 50A even if you try hard :P. It also resembles a 250W (U*I indeed to use the simple formula). The 3.3V line is probably more used in a modern system than the 5V line; think about PCI / PCI-E cards, chipsets and the Hot swap SATA (105.6W). So, those 2 lines combined will give you the total load, it´s about 60% of the totals, so let´s say 213W. Then we have the most important line, the +12V; 24A so you would say 288W but combining them with the other 2 lines you will get about 60% out of that max., making it a useful 173W. So, when we add up those 180W+230W we´ll have left a lousy 386W of those 600W AND a overdone 5V line with it´s 50A! A loss of more than 30%?; yes, that´s the marketing trick, cheap components to get high numbers and add some "extra" on top of that, not even thinking about how much it pulls away from your power outlet with it´s efficiency of 65% (unless you like to head up the place with it).

Now, with this “knowledge” we look at the Antec earthwatts EA380 I showed you.

Output +3.3V@20A,+5V@20A,+12V1@17A,+12V2@17A,-12V@0.8A, +5VSB@2.5A

hmm, now, that´s looks different in every way; They cut away of the not much needed 5V line and added an extra 12V line to get more power out of cheaper components but still giving about let’s say 28A real Amperes out of those.

So, let´s make the calculation here again:

3.3V at 66W

5.0V at 100W

12V1 at 204W

12V2 at 204W

Subtotal of 574, let´s say 2/3 can be used at max., leaving a REAL 380W.

I hope this clears it up a bit ;).

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never considered the PSU as a vital component with certain specs to look for.

It VERY much is, and not only when it comes to computers! You wouldn't believe how many systems I've seen who didn't work because of that (and again, I don't mean just computers here).

The physical lesson in high school on W, Amps, and volts isn't coming back to me.

There's just FAR more to it than just "what is wattage":

-you have to have power where it counts/where you need it. That junk PSU has way too many amps on the 5V rail (that screams old outdated design already, i.e. a classic early ATX era design), and not enough where you really want more i.e. the 12V rail(s)

-you have to understand how they're electrically built: often, different rails are powered from the same tap on the same transformer, so they'll claim X amps on a rail and Y amps on another, but both combined cannot exceed what the transformer's output can handle i.e. combined power limits, which are clearly missing on this unit (like on most junk PSUs where they'd rather you not know! more or less lying by omission here)

-a lesson in quality: cheapo PSUs use garbage components overall (everything to save a penny), like crappy capacitors and a lot of other inadequate parts (e.g. diodes & mosfets that cannot handle the advertised load, bolted right onto inadequate heat sinks no less) that will quickly fail

-a lesson in real-life conditions: perhaps they claim it can provide that much power, assuming the heat sink the parts rest on is at 20 degrees Celsius, with similar room temp. Too bad that in real life, the air getting in your PSU will be hotter, and the heat sinks hotter too. And some key components derate with temperature (loose capacity), so the real-life capacity just isn't what they claim (I've plenty of times seen junk PSUs where some parts couldn't handle half the current stated at "normal" operating temperatures)

-a lesson in marketing: wattages on garbage PSUs are often just plain old lies by their marketing department (they probably call it more like "being creative with math"). I've seen generic 600W PSUs die with a 350W load before -- it's not uncommon at all. Most generic PSUs fail WAY below the wattages they claim.

Take some time to read this (and laugh a bit). Then you won't ever consider buying another no-name/generic PSU anymore ever (I hope so anyways). Hint: the very first PSU tested (a 650W junk unit) dies at 184W of load... I wish I could say I'm surprised.

The better companies' products are a million times better. Not only they include good/useful/important features like Active PFC, 80+, better filtering, various optional protections and plenty of other reasons (better connector sets, modular designs, cleaner power, etc), but they can actually supply as much power as stated, in real-life situations (and high temps), where it counts/is needed. They will often pay for themselves, being 80+ and also by outlasting junk no-name units' lifetimes by a long shot.

Garbage PSUs sell very well. Because they're cheap, and most people don't see past the one number (wattage). Just like some people don't see anything else than the clock speed when buying a CPU, or the megapixels when buying a camera. That provides a strong [monetary] incentive for continuing to sell junk unfortunately.

Designing, building, testing and repairing SMPS'es is part of what I do for a living.

Edited by crahak
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Nice add crahak for the people that know a bit more

Thanks!

I just kept it simple ;).

Then I guess I tried to... :lol: But even then, there's just soooooooo much more to it. Group regulation? Overall assembly quality (e.g. lose screws)? How many 12V rails (and how they're "distributed" on different cables)? Nylon braid on the wires (and the gauge of the said wires)? Ripple? How god/quiet/effective the fan is (brand? sleeve or bearings)? What optional protections are there and how well do they work? Efficiency curves? ... We could go on for just about forever here.

With the nicer PSUs one pays for a lot more than just brand name. There's a GIGANTIC difference in quality too.

EDIT: Why don´t i see you online (MSN) any more crahak, or replies on my PMs :P.

Lack of time as always! Stuff to do around the house, a last minute near-deadline GDI+ app I gotta work onto, etc. My life is pretty crazy at times. I shouldn't even be "wasting" time posting here!

Edited by crahak
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Thanks for explanation. I did some of my own research and it's starting to make sense. At least now I know the specs I should be looking for.

I also learned that my old PSU is 20-pin and my MOBO supports 24-pin so the extra 4 pins have nothing in them. Recently, I removed my old PCI-E graphics card (ATI Radeon x600 series) and put it in this one. What I read was these extra 4 pins are used to supply power to the PCI-E. Perhaps, just perhaps, that had something to do with the current events?? But it's my mere presumptions.

Yeah, the Antec seems a lot better choice now. Should I go ahead and buy or wait for black friday in hope of it becoming cheaper - that is the question!!

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That particular battery is like the death-pill to any motherboard. Usually you can tell when the battery is failing -- not this one.
Interesting, I never had that. What motherboard are we talking about here?

Well, it was more than one motherboard, they were not exactly new (far from it), but one had a Via chipset, one had an Intel 8xx chipset. I've never had a battery kill a motherboard (temporarily) before, so it was a big surprise to find they wouldn't spin the fans or POST with that battery in.

Check out the Antec earthwatts EA380, 10 bucks more but worth 10 times more.

And it really does give 380 watts output. At 80% efficiency, it therefore draws about 475 watts from the mains. (Because 80% of 475 Watts is 380 Watts.)

Read the technical report: Antec_EA-380_380W_80PLUS_Report.pdf (one page PDF file).

The better companies' products are a million times better. Not only they include good/useful/important features like Active PFC, 80+, better filtering, ...

80 PLUS is always worth having. The extra purchase cost will be recovered in lower running costs. ActivePFC adds to the overall efficiency, too.

As always, learn the good brand names: Antec, Corsair, Enermax, Tagan, SeaSonic ... (everybody has their own favourites). No company is perfect, but none of those will explode at 50% power output, unlike the no-name brands.

_____

Also, don't get the 20+4 pin connector confused with the EXTRA 4 pin connector that also goes to the motherboard.

.

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Also, don't get the 20+4 pin connector confused with the EXTRA 4 pin connector that also goes to the motherboard.

I just happen to notice that today cause I opened my box. The EXTRA 4 pin connector actually does not connect to the last 4 pins part of the 24 pin connection because of the grooves.

Anyway, I opened it to test see if my working PSU fires it up and it did not. Something else is wrong. My CPU probably died from overheating. I had a hard time keeping it cool.

So... I'm gonna build a new one. I wanted to go ahead with the Core i7 but I noticed that it required the new DDR3 memory - it's gonna get too expensive so I'm going with a

Core 2 Duo E8400 Wolfdale (3.0 or 3.16 GHz) with either a Gigabyte GA-EP45-DS3R or ASUS P5Q Pro.

I can't decide on the MOBO because the one that died here (P5GDC-V) was an ASUS and it ran hot so I'm like afraid of ASUS but I don't know if they've improved. And my current Gigabyte runs really cool. But the ASUS as eSATA, which I want...

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But the ASUS as eSATA, which I want...

The GA-EP45-DS3R actually has two (on a bracket).

See the pic here

80 PLUS is always worth having. The extra purchase cost will be recovered in lower running costs.

No kidding! If your PC draws 200W average (24/7), and that you have cheap hydro power or such (at say, $0.10/KW*h), 80% (over a 70% model) will save you about $35 per year. So over its lifetime of say, 4 or 5 years, it'll more than pay for itself (around $175 saved over 5 years). Of course, average power used varies a lot, and so does the price of power from one place to another.

Edited by crahak
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The GA-EP45-DS3R actually has two (on a bracket).

Well, what do you know. I couldn't find a list of contents anywhere even on website. Sometimes what's pictured is not always in the box. But I downloaded the manual and it does state that the bracket is included!

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