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Time for new Power Supply?


GolfProRM

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I just added a DVD burner to my computer, and am wondering if I'm pushing the limits of my power supply.I haven't had any problems in Linux, but when I booted into Windows, I had an occurrence where my computer just shut off (instantly)... It only happened once, but I'm wondering if it's power supply rated.Here's my system specs:

Home PC      Brand: Home Built      Case: Generic      Power Supply: 300w Enermax      Processor: AMD AthlonXP 2000+       Motherboard: Gigabyte GA-7VA      Chipset: VIA KT400      RAM: 512 MB DDR PC2700 (333 Mhz)      Harddrives: 80Gb Western Digital 7200rpm ATA133                         30Gb Maxtor 7200rpm ATA133      Video: 128 Mb GeForce FX5600 8x AGP      Audio: Soundblaster Audigy2 LS      CDROM: 52x24x52 CD-RW drive      DVD+-RW: 12X Optorite Burner      Other: 6 USB 2.0 ports, 5 PCI slots, 1 8x AGP slot.      Keyboard: Microsoft Natural Multimedia Keyboard      Mouse: Microsoft Intellimouse Explorer 4.0A      Joystick: Logitech Wingman Extreme Digital      OS: SuSE9.1/Windows XP Pro

I don't really have a lot of money to spend on a new power supply, but if I need one, I'l get one. I'm open to suggestion as to what wattage to buy and what brands will give me the best bang for my buck.Help is appreciated! ;)

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Well... per that site, I get:Your Recommended Minimum Power Supply is 296 Watts!!Think I should upgrade?

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nlinecomputers

Yep. You too close to the limits. Especially as older power supplies tend to grow weaker and fail to deliver as much juice as they do when new.

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;) :happyroll: Welll......... with just 4 watts to spare ... I think it could might be a good idea... at least up to a 350 watt .... I know they have/had 320 watt PSU's at one time .. but I think a 10% cushion of the rated consumption rate about that would be sufficient.... maybe Nathan can jump in and give a view on this too ...
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Start at www.pricegrabber.com .... that will give you a good ball park to work from .... computer surplus.com ........... tiger direct

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nlinecomputers

Best way IMHO to judge a PSU is by weight. All other factors being equal the more the unit wieghs the stronger and more reliable the unit tends to be.I get my PSUs from directon.com because they are on of the few places that post the weight of the units.

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I'm partial to OCZ, Enermax, and Antec in that order. Try to get as much amperage to the 12 & 3.3 volt rails as possible for your buck. the Enermax PS's would probably be kind to your wallet and still perform well. As for where to buy, I now buy everything from new egg. The 520 watt OCZ is on my wish list ;) :happyroll: Link

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I'm partial to OCZ, Enermax, and Antec in that order. Try to get as much amperage to the 12 & 5 volt rails as possible for your buck. the Enermax PS's would probably be kind to your wallet and still perform well.  As for where to buy, I now buy everything from new egg. The 520 watt OCZ is on my wish list  ;)  :happyroll: Link
Now THAT'S a power supply!!!!It's only $125 on Newegg.com ;)I'm thinking about looking for one with a 120mm fan to help reduce some noise... will have to wait a week (need to get paid again) before I buy one.
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I was just over to Price Grabber and they have some PSU's ,, a true 450w for less than 60.00 but in going with Nathans comment about weight it was given in kg's 2.5 and I do not do well in converting that .. they did have an Antec 350w wt 5 lbs .. less than 40.00

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I read an article a while back that concurs with nlinecomputers weight argument.. More robust power supplies require heavier components like heat sinks...but I wonder how long it is before some of the bargain vendors start adding blocks of cheap metal in strategic places to beef up the weight :lol:When it comes to critical components like cooling, power supplies etc I follow the advice of the overclockers. They push their components to the limit, so anything that gets their nod is usually top notch stuff.This enermax Noisetaker is a decent midrange product ($80) it has seperate 12v rails for a total of 31 amps. LinkI was lucky enough to buy a case that came with a 120mm fan. It pulls lots of air and is extremely quiet. My other case has two 80mm and you can hear it across the room...I'm yanking them out in favor of one 120mm. The larger fans really make an incredible difference in noise.

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Cluttermagnet

2.2 pounds to the kilogram- so 2.5 kilograms is equal to 5.5 pounds. Hey, go get one of those free conversion utilities. There are a bunch of them. Plug in a number, give it the to and from units, and let it crank out the numbers. Or use a calculator and figure it yourself if you are feeling frisky. ;) I use Unit Converter v 1.05 by Johannes Wallroth, Berlin, Germany. Get it here. Click on the Download link and scroll down to Unit Converter. A small 80K freeware utility.

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I haven't had any problems in Linux, but when I booted into Windows, I had an occurrence where my computer just shut off (instantly)...  It only happened once, but I'm wondering if it's power supply rated.
Hi Ryan,Bit strange that Linux would run Ok and Win doesn't as I can't see Win drawing any more current than Linux for the hardware. :( You don't say what Win it is But, you can go into System Properties / Startup and Recovery / System Failure and De-Select Auto-Restart.Might be worth a try? :rolleyes:
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Best way IMHO to judge a PSU is by weight.  All other factors being equal the more the unit weighs the stronger and more reliable the unit tends to be.
Hi Nathan,Not a bad rough estimate, but correct never the less. :( To increase the amperage output of a transformer the Primary and Secondary windings must retain the same ratio of windings as a lesser wattage unit, the only thing that can be done to increase the amperage is to increase the size of the Copper wire used to wind the coils with. And of course this increases both the physical size and the weight of the transformer. The diodes used in the the bridge-rectifier are also higher rated and larger but don't really count for much extra weight, the same with some of the other components.That rough guide would extend to a 400w tranny being nearly double the weight of a 200w. :) Yep! I agree with what you say. :rolleyes:
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Hi Ryan,Bit strange that Linux would run Ok and Win doesn't as I can't see Win drawing any more current than Linux for the hardware. :( You don't say what Win it is But, you can go into System Properties / Startup and Recovery / System Failure and De-Select Auto-Restart.Might be worth a try? :rolleyes:
My system specs say what OS I'm running (I posted them in the first post)... It's WinXP Pro.I've got the Auto-restart shut off.I booted back into windows last night, and haven't had any problems since, so I'm wondering if it wasn't a loose power cord or something...-------------------------------------------------I've got my eye on a couple now...http://www.newegg.com/app/ViewProductDesc....-103-445&depa=0ORhttp://www.newegg.com/app/ViewProductDesc....-163-104&depa=0
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If it was my money I would go with the Enermax. It has dual +12v rails, 15amps(+12v1) & 14amps(+12v2). With dual 12v rails you are practically guaranteeing yourself stable voltages. I've noticed that mobos are getting very sensitive where clean stable power is concerned. It will be a plus if you ever outgrow your current motherboard. Will also be handy if you over clock, which requires stable power.The Siverstone is only suppling 18amps total to +12v. Which in my opinion is skimpy. One of my 350w Antecs delivers 16. I know that big fan is a plus, but the +12v rail gets drawn on by the Processor, optical & hard drives, as well as some case fans.
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The link to the power calculator was interesting. My max power requirements are 17 watts MORE than the max my power supply provides. And I don't have any problems.As the site warns:

Please Note: The Wattages listed below are maximum peak wattages for each component. The total amount this calculator figures is for all devices running at peak utilization. It is important to bear in mind that this amount will never be reached under typical operation.
I recall reading somewhere that you can generally take the number generated by power calculators like this and divide by 2 for real world approximate usage.It is good to have some headroom on power, but I think too many people get enamored over raw BIG numbers. It's the old stereotype, if a little is good, more must be better. People who put premium gas in cars designed to run on regular gas think similarly. They think a bigger octane number will make their car generate more horsepower. Ain't so!In terms of power for a computer, the QUALITY is most important. You want stead, clean power. Cleaning up the power before it reaches the power supply will help your system a lot, even if it has a cheap power supply.
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Your Gasoline analogy is partially incorrect as compares to Power supplies. A higher octane than recommended is a waste of money & will rob you of performance. The goal is have the lowest octane that will not cause the engine to knock. Anything more is a waste.Having a power supply rated higher than system spec is not a waste of money and will improve performance in most cases. Playing percentages with highly sensitive electronic equipment is a recipe for disaster. You are risking system stability and possible component failure. It should also meet future needs without problems.I've seen too many cases in which people get BSOD's, spontaneously rebooting computers, GPF faults, and wonder why. They have poured hundreds of dollars into their systems but balk at spending $65 on a component that powers all their devices, opting for a $10 piece of junk that came with the case.In this case more is better...and as I've said previously, rail amperage is just as important as wattage.

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Let's think logically here. You only need enough AMOUNT of power to cover your PEAK requirements. Anything more is of no value. As the previous quote from the original link says - most people will NEVER come near their peak. That would only happen if you were fully driving all your devices at the exact same time.I don't know for sure, but I'd guess that the bigger the power supply (in terms of wattage), the more power it consumes and the more heat it generates.The problem with the cheap power supply's is that they use low quality components and generate dirty power, with lots of spikes and variances. A better power supply will do a better job, but unless it is real high-end, most don't include power conditioning. And just because a power supply is 500 watts, doesn't mean it is better than a 350 watt one.

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As I've stated over and over, wattage is not the only concern. Buying a 500w power supply that delivers 14 amps max to +12v is going to be a problem.As a power supply runs, it tends to deliver less power not more, thus decreasing your headroom. A power supply that is close to capacity will work harder, be less efficient, generate more heat, and have a shorter lifespan.Ever hear the saying "penny wise, dollar foolish"? Power consumption for PC components is increasing, not decreasing. You will not be "wasting" you're money by exceeding your requirements. You will be ensuring that the PS bought today will easily meet your future requirements, not to mention stability for your current setup.Again, to spend $90+ on a motherboard, $120+ on a processor, $100+ on Ram, $250+ for optical and hardrives then decide to spend $10-20 for a power supply is illogical.Reading the following article may make things a bit clearer.http://www.extremeoverclocking.com/article...ly_Guide_1.html

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As I've stated over and over, wattage is not the only concern.  Buying a 500w power supply that delivers 14 amps max  to +12v is going to be a problem.
Hi NRD,Not really, it's only a matter of distribution.200w divided by 12v = 16.6 amps300w divided by 12v = 25.0 amps400w divided by 12v = 33.3 amps500w divided by 12v = 41.6 ampsAs you can see the amperage varies, then the current dividers come into play.Usually ceramic current-limiting resistors to distribute the current in such a way that the Mobo and the CPU always get a constant 8-10 amps, whatever.Using the 500w that leaves 21.6amps for distribution.The CPU & Chassis Fan 1 to 2.22a (26.64w) probably Max. (if it's not already included in the Mobo requirements)That leaves 19.38ASo you can see what I'm getting at. You would have to know the W/A rating of all the equipment you are running to calculate the required amperage to determine the minimum PS required.And ibe is right when he indicated that ALL of the peripherals are NOT all drawing operating-current at the same time and some are in stand-by-mode and drawing next-to-nothing.Amperage is a reservoir of power the PS is capable of producing....... If you are NOT drawing on it.... you are NOT using it.So 500w doesn't mean that you are using 500w.... you may only be using/drawing 300w.At least the PS won't be working very hard......... sort of a like Sherman Tank running in idle. :D But then again... Nice to know it's there if you ever need that bit extra.Higher amperage requirements also means thicker wiring... DC Current doesn't travel very well through thin cables. Or else, more distribution cables out of the PS. And depending on the way the PS is distributed, you would be better-off using ALL of the outlets for the peripherals rather than skimp-on extending them.
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I think you are incorrect. If I understand your post correctly, using your math a 420w power supply = 35 amp to 12v (420/12=35)Please take a look at the following image.LinkThis is a 420w power supply only providing a Max 16A. Where is the other 19a? and remember 16a represents MAX value. Did we forget about the other rails?Which brings me to another point raised here about not drawing the maximum value for each device. This is true, however that wattage rating on the side of your power supply represents its MAXIMUM output. To use that figure as a reference you would be foolishly relying on your power supply to operate at its maximum output at all times. Doing so will quickly end the productive life of the component not to mention voltage irregularities.I prefer to use the chart in the article I referenced. I will use the lowest watt rating and my system as modelAGP card = 30wPCI card = 5wNIC = 4wFloppy = 5wFANS = 9w (CPU, Chipset, Case)2 Optical = 20wIDE Drive = 5wMobo =25wRAM =64w (8w per 128mb)Athlon =70w-------------------------Total 237w X 1.8 =427w (X 1.8 to account for disproportionate draw on +12v rail)From site referenced previously (Link)"...For overall power supply wattage, add the requirement for each device in your system, then multiply by 1.8. (The multiplier takes into account that today’s systems draw disproportionally on the +12V output. Furthermore, power supplies are more efficient and reliable when loaded to 30% - 70% of maximum capacity..."As stated, I used lowest watt rating for each component. Choosing a middle figure raises the count considerably. You can count on the following to be used continously in a default system. Processor, Mobo, NIC, AGP, IDE, RAM, Fans. Even without the 1.8 multiplier, the total is 237w add a second hard drive, more case fans, lights, pci card, usb device etc and you are increasing the wattage requirements further. Please tell me again how a MAX 350w PS or a MAX 420w PS with weakly powered 12v rails is going to remain stable.

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Let's think logically here. ......And just because a power supply is 500 watts, doesn't mean it is better than a 350 watt one.
Well, lets do some math and see.I'll compare two power supplies from the same manufacturer. A 500w model and a 350w which can typically be found bundled in plain vanilla PC cases.Note, that ATX Power supplies can provide up to the Max of the combined +3.3 & +5 volt limit as long as the INDIVIDUAL current rating is not exceeded.First value is power rail, second is listed MAX Amps third is MAX Watt outputThe 350W+3.3v * 20a = 66 watts+5v * 30a = 150 watts+12v * 12a =144 watts+5v stndby * 2a = 10 watts-5v * 0.5a = 2.5 watts-12v * 0.8 = 9.6 wattsTotal = 150+144+10+2.5+9.6 = 316 MAX watts output(remember 66 watts excluded, as 150 watts is limit for 3.3/5v combination)So, that 350 watt power supply is only capable of producing 316 MAX watts of which 144 MAX is available to +12v, the hungriest rail in your system.Now the 500w+3.3v * 30a = 99 watts+5v * 45a = 225 watts+12v * 18a =216 watts+5v stndby * 2a = 10 watts-5v * 0.5a = 2.5 watts-12v * 0.8 = 9.6 wattsTotal = 225+216+10+2.5+9.6 = 463 MAX watts output(remember 99 watts excluded, as 225 watts is limit for 3.3/5v combination)So, that 500 watt power supply is only capable of producing 463 MAX watts of which 216 MAX is available to +12vSo in this case, I guess a 500 watt power supply is better. Consider the fact that the Processor is going to consume 70 watts from +12v add optical drives, IDE, Fans you are coming close to 144 MAX that the 350w power supply can out put. So as I said before, simply relying on the MAX wattage plastered on the side of the power supply is not enough. Rail amperage must also be considered. +12v being most important Will your PC still run? Sure. Will you be undervolting your components? Yep. Over time, as you continually push you PS to its limit, one of two things are probably going to happen...You will start getting mysterious errors, blue screens, spontaneous re-boots etc or you will push the power button and nothing will happen. In either case, I just hope that when your inadequate power supply does finally go, it doesn't take your Mother Board, Processor etc etc with it.I'm currently staring at a friends year old "AMD/Intel approved" 400w power supply with a nice, big black scorch mark on the back that I must replace because they instructed that "their computer is broke"Do as you wish.
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From site referenced previously (Link)"...For overall power supply wattage, add the requirement for each device in your system, then multiply by 1.8. (The multiplier takes into account that today’s systems draw disproportionally on the +12V output. Furthermore, power supplies are more efficient and reliable when loaded to 30% - 70% of maximum capacity..."
NRD, I can see that you are passionate about this, but I think you are wrong. Unfortunately, I don't know enough about electricity to contend on this subject.But by following the calculations at the link you provided, and using the 1.8 fudge factor, I should be running a power supply with 450 watts.Instead, my 4 year old Dell Precision 220 (a server level system) has a 230 watt power supply. It also had a 3 year warranty. I doubt that the people at Dell would put in an underpowered supply that would run close to the edge in a system that, back then, was intended to be sold to a business. Dell may piss all over regular consumers, but they know that they better not do that to a business.Since I've had this system, I have added a CD/RW drive, a 2nd hard drive and a sound card. All together, I've got:1 PIII 866 chip2x128 PC800 Rambus memory815 dual processor Intel mobo2 10K U160 SCSI drives1 IDE CD/RW1 IDE CD/R1 floppy1 video card1 sound card1 modem card1 86mm fanI don't get any weird errors, blue screens, etc. The system runs nicely. My REAL LIFE experience would seem to be in conflict with your theoretical posturings as to what will/might happen with such a low output power supply. I still believe that it is a rare person who needs a 400 or 500 watt power supply. What people do need is a GOOD power supply and IMO, a line conditioner or at least a good UPS (which cleans up the power but not as much as a separate conditioner).
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I think you are incorrect. If I understand your post correctly, using your math a 420w power supply = 35 amp to 12v  (420/12=35).
It's not my maths, it's a fact, it's an equasion that is constant irrespective of the W/V.Wattage divided by Voltage gives you the Amp-Hour.
This is a 420w power supply only providing a Max 16A.  Where is the other 19a? and remember 16a represents MAX value.  Did we forget about the other rails?
I wasn't being specific! as I said further down "that leaves 19.38A".Your picture also says 16A @ 12v, 35A @ 5v, 20A @ 3.3. While the last two seem high, just remember that as the voltage goes down the amperage increases. It also depends on how the AC transformer is coiled and tapped, or whether it's a single-tapped coil or Multi-Wound.Quote:As you can see the amperage varies, then the current dividers come into play.Usually ceramic current-limiting resistors (Edit: The big white thing in your picture, with additional V/R's to trim it) to distribute the current in such a way that the Mobo and the CPU always get a constant 8-10 amps, whatever.Using the 500w that leaves 21.6amps for distribution.The CPU & Chassis Fan 1 to 2.22a (26.64w) probably Max. (if it's not already included in the Mobo requirements)That leaves 19.38A End of Quote.edit: (to be distributed as they see fit for the 5v and 3v rail)
Which brings me to another point raised here about not drawing the maximum value for each device. This is true, however that wattage rating on the side of your power supply represents its MAXIMUM output. To use that figure as a reference you would be foolishly relying on your power supply to operate at its maximum output at all times. Doing so will quickly end the productive life of the component not to mention voltage irregularities.
Yea! you could probably cook an egg on it before it burns...... :P
Even without the 1.8 multiplier, the total is 237w  add a second hard drive, more case fans, lights, pci card, usb device  etc and you are increasing the wattage requirements further.
Yea! you also have to consider whether it's an inductive or resistive load also.
Please tell me again how a MAX 350w PS or a MAX 420w PS with weakly powered 12v rails is going to remain stable.
What are you calling 'rails', the little skinny tracks on the circuit board the the RED (positive) wire is connected to?Positive is only the resistive side of the load, it's the negative that carries the brunt, that's why its printed circuit is heavier.
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