Building a gaming PC

[Undertoad]

This thread is called Building a gaming PC. The HP/Dell engineered machines are absolutely meaningless on this thread.

The overall wattage number is just the added total of wattages on all rails. On gaming rigs the +12V rail is the most important, but power supply wattage doesn't break that down, so a higher wattage supply may still not provide enough power on that rail. Power supplies of 8 years ago aren't enough to run modern video cards. They draw huge amperage!

Power supplies are less efficient at 100%, do you care?

Now about upgrades. Going to overclock? Many gamers do! But never the HP/Dell engineered systems.

Going to RAID? Many gamers do! But never the HP/Dell engineered systems.

Going to have 8 sticks of memory? Many gamers do! But never the HP/Dell engineered systems.

Add memory, overclock, add a second high-end GPU and run in tandem with CLI, now you need twice the wattage on that +12V line and the 650W won't handle it.

Not only that but! As power supplies are used, they lose capacity due to electrolytic capacitor aging. What was an appropriate supply this year will likely have 20% less capacity next year.

Finally, the power supply companies lie about their numbers.

Hell, go with the 750W. You're not going to draw more wall power; actually probably less, as the unit will run more efficiently. And it may even be able to power next year's model GPUs.

[lumberjim]

And think of how big your penis will look!

[glatt]

And with all that extra heat pumping out, it won't be playing hiding turtle from the cold.

[lumberjim]

[Undertoad]

Getting a layman to add those numbers is virtually impossible for a majority. Simpler to tell him he needs a 600+ watt supply and sell him an 800 watt supply for a computer that never consumes even 300 watts.

No adding required, just go here, or to any other the other power calculators on the net, googlable with the phrase "pc power supply calculator".

Putting in the chosen components, allowing 3 high-performance fans and 3 USB power drawn devices (conservative in this day of USB charging), and with a 20% figure for capacitor aging, and overclocking a bit, the Thermaltake calculator says 476W is advised. We are giving headroom for additional components/USB charging and for enough amperage on the +12V rails.

Y'ever look at a video card in the last five years tw? They are massive. Take up more space than any other component and have their own dedicated rail. They are often as powerful and have as much memory as the motherboard. That's why it's a gaming rig, the type that HP/Dell generally do not sell.

[tw]

Originally Posted by Undertoad

No adding required, just go here, or to any other the other power calculators on the net, googlable with the phrase "pc power supply calculator".

A perfect example of why computer assemblers need 600+ watt power supplies for a system that only consumes 200+ watts.

We know that IDE disk drives can be powered from a USB port. That means a drive cannot draw more than 2.5 watts maximum. I added one IDE disk drive to the calculator. Not even an IDE interface card. Wattage increased from 88 to 105 watts. Had I added the interface card, it might have added another 14 watts. It says my disk drive consumes 17 watts? A 5400 RPM disk must not even consume 2.5 watt? How can this be if the calculator is so responsible and useful?

A disk drive interface card does not consumer 14 watts. It does not even consume half that.

The calculator also says these are continuously available - not maximum - numbers. So a disk drive that at maximum can only consume 2.5 watts may (according to the calculator) consume more than 17 watts? And its interface also is a toasty 15 watts? Yes. That is what the calculator says. Overly excessive numbers so that the power supply will be grossly more than required.

Thermaltake is selling power supplies to computer assemblers whose eyes glaze over with numbers. Your calculator says a less than 2.5 watt drive consumes more than 17 watts. Another example of why computer assemblers recommend 800 watt supplies for systems that barely consume 200 watts.

But again, wattage is useless for defining power requirements. Current draw for each voltage is relevant. Since consumers and that calculator cannot do that, then all simply provides a wattage numbers that is twice (or six times) more than required.

How many watts does the gaming video card consume? Telling us that the number is big is classic junk science. What exactly are the numbers for video cards in the past five years? As I say often and bluntly, useless claims have no numbers. Informed claims also provide perspective. How much current for each voltage was and is now required for video cards?

Demonstrated by the power supply is why so many recommendations for computers are often uninformed. How to separate the useful recommendations from hearsay: subjective and bogus claims provide no numbers. Or hype numbers from hearsay without any reasons to believe those numbers. Due to so much knowledge from hearsay, the same computer using a 200+ supply provided by engineers is also found with an 800 watt supply recommended by computer assemblers informed by a Thermaltake calculator. A majority will recommend an 800 watt supply. And other unnecessary components.

[glatt]

How many watts does the gaming video card consume? Telling us that the number is big is classic junk science. What exactly are the numbers for video cards in the past five years. Wild speculation and junk science says it is large - a useless claim because it is subjective. Honesty demands that claim include a number.

I thought we covered this.

http://www.asus.com/Graphics_Cards/G...specifications

"Power Consumption:
up to 225W2 additional 6 pin PCIe power required"

If you don't trust the manufacturer, then how are you going to get that number? Pay for the thing and then test it? Ain't nobody got time for that.

[tw]

Originally Posted by glatt

I thought we covered this.
"Power Consumption:
up to 225W2 additional 6 pin PCIe power required"

That is not the power it consumes. That is an inflated number that customers are told. If the spec was written for a designer, it lists amperes for each voltage. Why is nobody's computer toasting bread? That question alone demonstrates wide variation between what is actually needed verses what a majority recommend.

The card may consume just over 100 watts. So we tell the computer assembler to provide a supply with an additional 225 watts. An example of why reality and what most computer assemblers recommend often varies significantly for other computer parts. We can also discuss another popular myth associated with Arctic Silver.

[glatt]

Originally Posted by tw

That is not the power it consumes. That is an inflated number that customers are told.

So how, specifically, do you find the real number?

[tw]

Originally Posted by glatt

If you don't trust the manufacturer, then how are you going to get that number? Pay for the thing and then test it? Ain't nobody got time for that.

Nobody said the manufacturer is lying. He has simply added a safety margin due to who his market is.

One can easily learn what the numbers really are by measuring. So many did that to learn their computers mostly consume around 100 watts. Most computers rarely exceed 200 watts in full load operation. One actually got his gaming computer to consume 400 watts.
What is your desktop power usage while browsing these forums?

41 watts idle - 109 watts running Prime95

Someone blamed the measuring device because numbers did not agree with popular hearsay:
I have proved Kill-A-Watt accuracy .. NOT GOOD.

at idle I was sitting at 65W and it peaked at 102W booting up.

These people obtained real world numbers. And that is the point. They got facts. Whereas most who recommend computer parts only recite popular hearsay. Always take what the majority recommend with a grain of salt. Especially when claims are subjective - not tempered by numbers. Demonstrated by the PSU is why so many myths are so often believed - ie Airborne cures the common cold or Geritol for a longer life.

If that video controller spec is useful, then it cited current (amperes) for each volt. Computer assemblers are told to get a power supply at least twice as large as necessary. A 200 watt computer needs a 400 watt supply. To avoid clogging help lines. Thermaltake may then recommend a 600 watt supply. Then consumers know they need 800 watts.

[lumberjim]

Is there any reason NOT to go with a power supply that provides more than what's strictly needed? I chose the 800 on the recco of the guy at Tiger Direct. I had a power supply fail in a Dell computer once, and did not want a repeat of that experience. I may very well upgrade my rig in future. The price difference was not prohibitive as I recall. Why are we spending so much time on this? Just tw wanking about how stupid everyone else in the world is, as usual? Thought so.

[tw]

Originally Posted by lumberjim

I chose the 800 on the recco of the guy at Tiger Direct. I had a power supply fail in a Dell computer once, and did not want a repeat of that experience.

That is also another popular myth. More watts means a more reliable power supply. Not true. In fact many power supplies have less stress when operating at closer to 100% power. Some technology supplies are at greatest stress when at 50% rated power.

But hearsay (and no numbers) easily convinces many that more watts mean better reliability.

[Undertoad]

If you don't like Thermaltake, try any of the 30 other power calculators.

[Undertoad]

Of course, and did you ever see one of those in an HP/Dell configuration? You can't even get one of those into the flipping case!

[Undertoad]

The EVGA GeForce GTX 660 has a minimum requirement of 24 amps on its own 12V+ rail.


watts = amps x volts OR P=IE as I learned it