Some questions about PSUs...

Michael19xx

Baseband Member
Messages
32
Location
United States
  1. Will a higher wattage PSU cause my power bill to go up?

  2. Which of the 80 Plus standards should I aim for in terms of best value to efficiency ratio? Bronze, Silver, Gold, or Platinum?

  3. If the parts inside of my computer do not draw 1000W, would my PSU continue to draw that much power from the wall anyway?

  4. Is it okay to reach 90%-100% load on a daily basis?


Thanks in advance!
 
Last edited:
1. Will a higher wattage PSU cause my power bill to go up?

2. Which of the 80 Plus standards should I aim for in terms of best value to efficiency ratio? Bronze, Silver, Gold, or Platinum?

3. If the parts inside of my computer do not draw 1000W, would my PSU continue to draw that much power from the wall anyway?

4. Is it okay to reach 90%-100% load on a daily basis?


Thanks?

To answer your questions:

1. That isn't necesarily true. Your amount of components you have and how much power they draw will determine how much your power bill is.

2. You can't go wrong with any of the 80 Plus standards.

3. Simple answer, no. The 1000W on your PSU is the maximum amount of power that the PSU is capable of outputting. It is not necesarily and indication of how much power the PSU will draw from the wall at a given time.

4. It is, but I wouldn't feel comfortable doing it. I like to have headroom because as components age, they will draw more power and conversely, the PSU will output less power. When I'm building a system, I like to use a PSU that is rated for at least 125% of the wattage the components will draw. For example, if I build a rig that has components that draw 500W, I will use a PSU that is capable of outputting at least 625W.
 
So, the only reason to shy away from a higher wattage PSU would be cost, correct? And in buying a PSU that has a higher wattage rating, you're given much more headroom for upgrades, and the system is far safer from drawing more wattage than the PSU can handle (If theres a term for that, please let me know)?

Is this correct?
 
So, the only reason to shy away from a higher wattage PSU would be cost, correct? And in buying a PSU that has a higher wattage rating, you're given much more headroom for upgrades, and the system is far safer from drawing more wattage than the PSU can handle (If theres a term for that, please let me know)?

Is this correct?

Correct, cost is the only significant factor.

However, more watts = more headroom, the unit will run cooler, as it ages you won't deal with it no longer being able to support your components, more upgradability, etc.

For the 80+ Bronze/Silver/Gold/Platinum etc. I'll try to explain.

The rating system is how efficient the power supply is. Efficiency being the relationship between input and output. A more efficient power supply will lose less input as heat than a less efficient power supply. For example (all numbers made up in this example), if PSU-1 is 80% efficient, and PSU-2 is 90% efficient, and your components draw 800W of power, then PSU-1 will have to draw 1000W from your wall to provide your components with 800W of power, where PSU-2 would only have to draw ~889W. So, over time, a more efficient unit will pay back in your power bill.

However, if you only run your computer a few hours a day, this may take YEARS to pay for itself, if it ever does. The more often you use your computer, the more attractive a higher-efficiency unit will look. 80+ Bronze, 80+ Silver, 80+ Gold, etc. just refers to different certified efficiencies (tested by 80 Plus).

80+ means the unit has been tested to 80% (or higher) efficiency at 20%, 50%, and 100% loads.

80+ Bronze = 82%
80+ Silver = 85%
80+ Gold = 87%
80+ Platinum = ...92%? I think
 
Correct, cost is the only significant factor.

However, more watts = more headroom, the unit will run cooler, as it ages you won't deal with it no longer being able to support your components, more upgradability, etc.

For the 80+ Bronze/Silver/Gold/Platinum etc. I'll try to explain.

The rating system is how efficient the power supply is. Efficiency being the relationship between input and output. A more efficient power supply will lose less input as heat than a less efficient power supply. For example (all numbers made up in this example), if PSU-1 is 80% efficient, and PSU-2 is 90% efficient, and your components draw 800W of power, then PSU-1 will have to draw 1000W from your wall to provide your components with 800W of power, where PSU-2 would only have to draw ~889W. So, over time, a more efficient unit will pay back in your power bill.

However, if you only run your computer a few hours a day, this may take YEARS to pay for itself, if it ever does. The more often you use your computer, the more attractive a higher-efficiency unit will look. 80+ Bronze, 80+ Silver, 80+ Gold, etc. just refers to different certified efficiencies (tested by 80 Plus).

80+ means the unit has been tested to 80% (or higher) efficiency at 20%, 50%, and 100% loads.

80+ Bronze = 82%
80+ Silver = 85%
80+ Gold = 87%
80+ Platinum = ...92%? I think

When I said cost, I meant cost of the unit, not cost of the power bill. The only reason to shy away from high-wattage PSUs would be the cost of the actual power supply itself, and not the cost of the electricity it would draw. Correct? Is this what you meant, too?

If my system needs 600W, the PSU will only provide 600W. And then, when it needs more, it will supply that amount. Is this correct as well?
 
When I said cost, I meant cost of the unit, not cost of the power bill. The only reason to shy away from high-wattage PSUs would be the cost of the actual power supply itself, and not the cost of the electricity it would draw. Correct? Is this what you meant, too?

If my system needs 600W, the PSU will only provide 600W. And then, when it needs more, it will supply that amount. Is this correct as well?

Correct & correct.

Even if you had a 2000W PSU, if your components only draw 600W of power, your unit will only provide 600W of power, and will be working under ~34% load. It simply has the capability to draw more power if needed.
 
Last edited:
Back
Top Bottom