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April 23

POWER SUPPLY

My computer comes with a 350 watt power supply. That seems like an awful high number of watts to be drawing all the time. How does it work? Does it only go to 300 watts when you use it? Also, how many watts does an intel "i5" CPU use? Would a 300 watt power supply be enough for a motherboard (with integrated intel graphics), i5 CPU, and one hard drive?

A PC power supply is a switched-mode power supply, which means it draws more power from the mains when more is drawn from it (unlike a linear regulator, which always draws the max and has to discharge what you don't need as waste heat). Different power supply models aim for varying levels of efficiency - yours will probably be labelled with the standard(s) its manufacturer aims for - see 80 Plus for some examples. -- Finlay McWalterᚠTalk 12:39, 23 April 2015 (UTC)[reply]

List of CPU power dissipation figures lists the power use of many CPU types, including i5s. Your motherboard manual will give the power use of the motherboard itself. -- Finlay McWalterᚠTalk 12:41, 23 April 2015 (UTC)[reply]

(edit conflict) 350W indicates the maximum load that the PSU can support, just like a 1,000 bhp car engine doesn't always produce that amount of power unless the accelerator is full depressed. Over-specifying the PSU won't do any harm, it's just more expensive to buy that needed. LongHairedFop (talk) 12:42, 23 April 2015 (UTC)[reply]

You can look up the manufacturer's datasheets for the specific drive you want, in order to get the max power draw for the drive you're considering. The drive will typically consume most power on spinup, and when it's under full load. To give you some ballpark figures, this Seagate pulls up to about 8W. 5400rpm drives will typically be a little bit less. -- Finlay McWalterᚠTalk 12:55, 23 April 2015 (UTC)[reply]

Ideally, one needs a power supply to work at about 80% of its rated capacity. Not only do you have the start up current drain but the manufacture expects you to add other hardware at some time. Additions may only add a few watts here and their but it would look bad on them if their machines gave up the ghost as soon as the customers added a scanner, printers, web cam, 3D printer, USB hubs etc. It is like driving your car at max speed all the time – the engine will not last very long. Look no further than rally and racing cars.. one race and the engine's nakered. Electronic components likewise age according to the load placed upon them.--Aspro (talk) 17:08, 23 April 2015 (UTC)[reply]

A Power supply unit (computer) need to cover peak loads. Electrolytic capacitors are the limiting factor in the livetime of a PSU. The higher the load and the higher the temperature, the shorter the is livespan. --Hans Haase (有问题吗) 23:36, 23 April 2015 (UTC)[reply]

The older the capaciors inside the PSU and on the M/B are, the less peak loads can be covered to prevent brownouts, causing repeating of data transfer due checksum errors or malfunction like freezing or bluescreens. --Hans Haase (有问题吗) 10:04, 25 April 2015 (UTC)[reply]

What type of phone/camera/camcorder was used to record the first YouTube video

Today is 10 years since Me at the Zoo. I didn't see in the article what was used to take the video. Peter Michner (talk) 14:22, 23 April 2015 (UTC)[reply]

Watts

How can I tell how many watts my computer is using from within Windows? I don't want to buy an external watt meter. Thank you

I doubt if your PC can tell you that. The best you could probably do, without a watt meter, is to look at the electrical meter for the house. That should show you the wattage you are using, if it's a digital meter. The old analog meters with spinning dials are a bit harder to use (there you would need to note the position of the dials before and after a fixed period of time and do some math). So, in theory comparing the house wattage with the PC on and off will tell you how much it is using. However, this can be complicated by some devices turning on and off periodically, like refrigerators, air conditioners, and furnace fans. So, you might want to unplug the fridge and turn the thermostat so the A/C and furnace won't run during the test. Don't forget to plug the fridge back in ! StuRat (talk) 16:19, 23 April 2015 (UTC)[reply]

If you are concerned about power use, get a power meter (like Kill-a-Watt). You'd be surprised how many things suck power. My old TV used more power when it turned off than when it was turned on! I replaced it, naturally. I also located a lot of other things that suck too much power and either put them on a power switch (to keep them from sucking electricity when I wasn't using them) or replaced them. For a computer, you can see how much power is used over a period of time and see how it changes from doing something like surfing the web to something else like playing video games. 209.149.113.201 (talk) 17:17, 23 April 2015 (UTC)[reply]

Another very approximate way to tell what is using power is what gets hot, since most power eventually ends up turned into heat. StuRat (talk) 18:23, 23 April 2015 (UTC)[reply]

Don't say that on the Science Desk. They are adamant that ALL power becomes heat. 209.149.113.201 (talk) 18:42, 23 April 2015 (UTC)[reply]

Is that why, the more powerful the politician, the more hot-air they spout? - Just wondering--Aspro (talk) 20:17, 23 April 2015 (UTC)[reply]

Well, yes, by not heat within that particular appliance. Some energy escapes as sound and light and becomes heat somewhere else. StuRat (talk) 05:00, 24 April 2015 (UTC) [reply]

'Everest Ultimate Edition' software, or latest version. I recall the software doing something to do with 'mw' -- Mr. Prophet (talk) 18:51, 23 April 2015 (UTC)[reply]

EUE was replaced by AIDA64. It has a database of power consumption averages for CPUs and GPUs. From that, it estimates power draw over time based on the CPU/GPU configuration it detects in your system. For the money ($40), I'd get a Kill-a-Watt ($20) and get an rather exact measure of power consumption. 209.149.113.201 (talk) 19:21, 23 April 2015 (UTC)[reply]

No way. DePending on the load a computer needs more or less energy. The PSU also has a varable efficency pening on age, load and type. You will need to use a wattmeter or monitor the AC input. --Hans Haase (有问题吗) 20:31, 23 April 2015 (UTC)[reply]

"Pending"/"pening" = "Depending" ? StuRat (talk) 04:58, 24 April 2015 (UTC) Yes, thank you. --Hans Haase (有问题吗) 07:11, 24 April 2015 (UTC)[reply]

The power consumption is exposed through the ACPI bus; this is how laptops read their battery status. There's a Linux programs that will show you the usage [1]; I'm not sure if anyone has written one for MS-Windows, but IIRC, the ACPI bus can be read by user-mode MS-Windows programs.

The API is described here, should you (or anyone else) wish to write a program. LongHairedFop (talk) 09:18, 24 April 2015 (UTC)[reply]