Cheap power supply vs good one?

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kbeam418
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The post sounds dumb but Is there really any point of getting expensive psu vs getting a no name? I would like all of your guys is opinions.

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ChocolateMiwk
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A power supply runs the whole computer. So basically, if the power supply fails, your computer fails. Generally, if a power supply fails, it could potentially take one of the components in the computer with it (CPU, GPU, HDD, etc). That is why most people do not recommend cheap power supplies because they are generally made with inferior parts and hence have a higher potential of failing.

The general rule is to not skimp out on your power supply.

KoutaFG
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Don't ever go cheap on a powersupply, its just one of those parts that its a 100% must buy band name part, go cheap and you'll regret it big time, the power supply, its one of the parts that usually when it really goes down, it takes other parts with it and in some cases, takes down all other parts and in extreme cases, takes your house to, by that I mean burns it down.

So my suggestion is, buy Corsair get at least 600w

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eire1274
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Okay, a breakdown:

Simple power supplies are just basically an inverter, taking higher-voltage AC to low-voltage DC.

The more complex it becomes, we start to see other features:

1) Rail separation: a basic power supply has 3 rails, one each at 3.3V, 5V, and 12V. The better the power supply, the more broken apart it is, and having multiple rails allows smaller, more stable components (consider 400W 12V on a single rail, compared to 2, 3, or 4 rails), and the smaller the load the less heat and flux you will see.

2) Power factor correction: digital controls help the power supply deal with power dips and peaks on the AC side, as well as changes in internal draw and flowback. Power supplies with passive PFC just have simple analog circuits which help maintain correct output voltages; machines with active PFC have digital circuits for the same purposes, but tend to be a lot faster in correction. PFC both extends the durability of the PSU, and also helps prevent the little voltage glitches that tend to be the early death of our components.

3) Power efficiencies and EMI: You will see lots of PSUs sporting 80-Plus badges, bronze, silver, gold, and platinum. What these mean is how efficient the system is in converting the power over, and the better it is, the cooler it is, the more stable it is, and above all draws less power to do its job. Electo-Magnetic Interference protection, which usually is embedded in 80-Plus supplies as well as higher-quality PFC systems, keeps the inverter from projecting a magnetic field, and also prevents external fields from interfering with it. Again, we are looking at stability, and this can also be very good for overclocked systems as it creates a more stable electrical environment.

4) Weight. Now, initially, why would you want your PSU heavy? First off, heatsink systems and overall cooling just isn't a way to save weight, and a cool PSU means a much more stable system. Secondly, solid-core components are much heavier than the cheaper hollow-core, and solid-core capacitors are far more stable, last longer, and generate a more reliable output.

Going on, there are hundreds of more design features that we could go over, but they tend to all follow the above 4. Spending more on a PSU with a high reputation is NOT A BAD IDEA, as a solid PSU is just the first step in building a system that will outlive its warranty. Just stepping from a $20 unit to an $80 unit, in reference to a $1000 build is a relatively small expense, but can save you so much worry in the long run.

Nick McDermott

Prophet4NO1
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eire1274 wrote:Okay, a breakdown:

Simple power supplies are just basically an inverter, taking higher-voltage AC to low-voltage DC.

The more complex it becomes, we start to see other features:

1) Rail separation: a basic power supply has 3 rails, one each at 3.3V, 5V, and 12V. The better the power supply, the more broken apart it is, and having multiple rails allows smaller, more stable components (consider 400W 12V on a single rail, compared to 2, 3, or 4 rails), and the smaller the load the less heat and flux you will see.

2) Power factor correction: digital controls help the power supply deal with power dips and peaks on the AC side, as well as changes in internal draw and flowback. Power supplies with passive PFC just have simple analog circuits which help maintain correct output voltages; machines with active PFC have digital circuits for the same purposes, but tend to be a lot faster in correction. PFC both extends the durability of the PSU, and also helps prevent the little voltage glitches that tend to be the early death of our components.

3) Power efficiencies and EMI: You will see lots of PSUs sporting 80-Plus badges, bronze, silver, gold, and platinum. What these mean is how efficient the system is in converting the power over, and the better it is, the cooler it is, the more stable it is, and above all draws less power to do its job. Electo-Magnetic Interference protection, which usually is embedded in 80-Plus supplies as well as higher-quality PFC systems, keeps the inverter from projecting a magnetic field, and also prevents external fields from interfering with it. Again, we are looking at stability, and this can also be very good for overclocked systems as it creates a more stable electrical environment.

4) Weight. Now, initially, why would you want your PSU heavy? First off, heatsink systems and overall cooling just isn't a way to save weight, and a cool PSU means a much more stable system. Secondly, solid-core components are much heavier than the cheaper hollow-core, and solid-core capacitors are far more stable, last longer, and generate a more reliable output.

Going on, there are hundreds of more design features that we could go over, but they tend to all follow the above 4. Spending more on a PSU with a high reputation is NOT A BAD IDEA, as a solid PSU is just the first step in building a system that will outlive its warranty. Just stepping from a $20 unit to an $80 unit, in reference to a $1000 build is a relatively small expense, but can save you so much worry in the long run.

----------

I can not agree with the first part. Nearly every high end PSU on the market uses a single 12v rail. Event he Seasonic Platinum rated ones, all Corsair, all the top level OCZ, Sparkle, I can go on. They claim higher efficiency is possible and higher reliability. Multiple rails are not needed till getting well past 1000 watts. I will take the word from the top level builders and suppliers of PSU's over any one else. No offence. But there is a reason they all do this for the best and most expensive PSU's.

eire1274
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Prophet4NO1 wrote: "I can not agree with the first part. Nearly every high end PSU on the market uses a single 12v rail. Event he Seasonic Platinum rated ones, all Corsair, all the top level OCZ, Sparkle, I can go on. They claim higher efficiency is possible and higher reliability. Multiple rails are not needed till getting well past 1000 watts. I will take the word from the top level builders and suppliers of PSU's over any one else. No offence. But there is a reason they all do this for the best and most expensive PSU's."

Please note that I was stating features that can be found in more expensive PSUs, not features that every expensive PSU has.

I'd recommend reading development papers from Corsair, OCZ, and Seasonic on multiple rail technologies. Many "multiple rail" systems are a single 12V inverter seperated into channels by capacitance (note: most super-high end enterprise equipment is actually multiple inverter). The reason to do this is so that hard disk spin-up (or shifting in green hard disks) or GPU power variance doesn't introduce voltage drop due to amperage consumption. This is an industry standard for heavy wattage conversion.

Nick McDermott

kbeam418
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I have a Bestec in my Dell Inspiron 531s. It's a 250w psu, it also has multiple rails. What I'm wondering is if I should go with won of the name brand psu's.

Prophet4NO1
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Dell is notorious for using crap PSU's. Don't get another one.

kbeam418
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Prophet4NO1 wrote:Dell is notorious for using crap PSU's. Don't get another one. Got it for free, I'll be building my next computer.

mrperfect44550
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In my thoughts if it meets your stander always save money, u never know when u need it for other purpose or upgrade. if want features, quality, flexibility or other perks u gonna end up narrowing down your search result to a good sold one. but its not necessary, thinking- 1) what else r u gonna get from a psu beside power to computer. thats the main purpose 2) how often you clean or tweak your hard drive. but its always good a good source and plus power for future upgrade reference.

Petertherock18
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Please don't go out and search for cheap named power supplies. There are many good brand name power supplied out there that have excellent performance for your buck. Just do some research. You don't want a PSU that could fail or burn out and damage any other pc components , trust me.

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MikeIllusion
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Many cheap POS power supplies tend to be very unreliable and unpredictable, definitely not something you want to cheap out on if anything at all.