Project Reality Forums

So just a quick question because with the hardware I have it just does not seem to draw the right power at full load. I'm just concerned my PC is not running at full capacity sometimes.

Specs below:
Intel i5-2500k overclocked at 4.5GHz
NVIDIA GTX 680 (drawing a blank on the brand)
ASUS P8Z68-V Motherboard
12 GB RAM (something like 1366 I think)
4 Samsung Spinpoint F3's 7200rpm
OCZ Synapse Cache 128GB
Cougar 750 watt PSU
Acer 23" 1920x1080 monitor

Let me know if I forgot any important parts.

I run this entire system through a surge protector and then have a Kill-a-Watt plugged in between. The highest reading I have ever seen this computer use is below 400 watts. It has never exceeded that number. It will idle at like mid 200's usually. Is there any problem with my system not using enough power?

You should be able to find the power usage of all the parts in your system. Then just add it up and you should have a good idea on what it should be pulling.
just a quick check:
your HDD's pull about 8 watts/ea during read/write
Your CPU showed about 162watts stock(unclocked) 311watts to 5Ghz.

sources:
source-1
source-2

Having a larger than necessary power supply is good. Your system will not pull enough to stress it or make it fail.

How many fans in the case? Any USB peripherals drawing power, etc?

This can be a boring conversation but you are a engineering major so maybe it interests you,

Check out the graphs and the paragraphs explaining them here:
Power Supply Efficiency Myths - Power-Supplies-PC-Cases-Case-Mods - CPU-Components

ALL PSUs have an efficiency curve, X axis is either % of rated Watts or actual Watts, Y axis is efficiency. Most PSUs are most efficient on the 12V rail at 50 to 55% efficiency,

Your PC draws just around 380 to 420 Watts, just guessing, and you should be near the peak of your efficiency curve.

I bought a rather unknown PSU knowing it was only 80+ rated but right at the peak efficiency it is 93% efficient, and my system sits at Wattage draw at or very near peak efficiency.


The online PSU Watts calculators always try to upsell more expensive PSUs,
justified as:
1. When the system first boots, it draws maximum wattage until the BIOS takes control of the hardware.
2. The efficiency argument above
3. Buffer to prevent idiots from burning out OEM PSUs that are marginally rated to the online calculators
4. Almost all PSU manufacturers incorrectly rate their PSUs
3b. Electrolytic capacitor aging. When used heavily or over an extended period of time (1+ years) a power supply will slowly lose some of its initial wattage capacity. We recommend you add 10-20% if you plan to keep your PSU for more than 1 year, or 20-30% for 24/7 usage and 1+ years.

eXtreme PSU Calculator

Send To Printer Back To Calculator

Notes: (Only text visible within note field will print.)



System Type: 1 physical CPU
Motherboard: High End - Desktop
CPU Socket: Socket LGA 1155
CPU: Intel Core i5-2500K 3300 MHz Sandy Bridge
Overclocked: 4500 MHz, 1.3 V
CPU Utilization (TDP): 90% TDP
RAM: 4 Sticks DDR3 SDRAM
Video Card 1: NVIDIA GeForce GTX 680

ATTENTION: FOR PERSONAL, NON-COMMERCIAL USE ONLY
IDE HDD 7200 rpm: 4 HDDs
DRAM SSD: 1 Drive
DVD-RW/DVD+RW Drive: 1 Drive
USB: 2 Devices
Fans
Regular: 4 Fans 120mm;
Keyboard and mouse: Yes
System Load: 100 %

Minimum PSU Wattage: 494 Watts
Recommended Wattage: 544 Watts

http://www.extreme.outervision.com/PSUEngine

Now that I'm on my computer I idle at 150 watts. So I guess that is a good number. I will check out all of those links you guys gave me. Thanks for the help so far, I shall report back.

Steeps5 wrote:I run this entire system through a surge protector and then have a Kill-a-Watt plugged in between. The highest reading I have ever seen this computer use is below 400 watts. It has never exceeded that number. It will idle at like mid 200's usually. Is there any problem with my system not using enough power?

Seems right to me

Geforce GTX 680 review - Hardware installation - Power consumption

Measured power consumption -

System in IDLE = 144 W
System Wattage with GPU in FULL Stress = 307 W
Difference (GPU load) = 163 W
Add average IDLE wattage ~10 W
Subjective obtained GPU power consumption = ~ 173 Watts

Steeps5 wrote:Now that I'm on my computer I idle at 150 watts. So I guess that is a good number.

Only relevant number for selecting a power supply is current (amperes) for each DC voltage. But most computer assemblers have no idea what is needed or what those numbers mean. So we simplify it. Ballpark calculate what power is needed for each DC voltage. Then tell the assembler a number that is at least double too large.

Most all computers consume less than 200 watts and rarely more than 350 for a very short period. So a computer assembler is told he needs at least 700 watts. Then any one voltage is guaranteed to provide more than enough current (amperes).

Your less than 200 watt number is quite normal for what so many assume are high performance gaming computers. After all, how many computers output heat like a four slice toaster? None.

Computers don't consume 500+ watts. Therefore computers designed by engineers typcally have 250 or 350 watt supplies. But similar computers built without doing calculations will often have 600 or 800 watt supplies.