TriEclipse
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See bottom of post for links to more information in this thread.
Lets talk about how much power AN ENTIRE 8800GTX SYSTEM consumes.
Clicking on this link will take you to a DailyTech article exploring the 8800GTX. In this review, they will also look at how much power an 8800GTX consumes. Look near the bottom, that's where you will find the power consumption. You will also find these specs;
* Intel Core 2 Extreme QX6700
* NVIDIA nForce 650i SLI based motherboard
* 2x1GB PC2-6400
* NVIDIA GeForce 8800GTX
* Western Digital Raptor 150
Now note this; Incase you didn't read the article, they mention that the power being measured is from the wall, meaning that the actual power supplied to the components is less, after factoring in the PSU efficiency. They are using a Power Supply that has an efficiency rating of 85% (excellent). And incase anyone's curious, they're using a Kill-A-Watt power meter to measure the power that their system's pulling in (again, from the wall).
That means that while they are measuring 321W out of the wall for the entire system, the actual power that the system is pulling in is (321W x .85) = ~273 W. 273W power consumption for a system with a Quad Core processor, high-end motherboard, 2 Gigs of RAM, an 8800GTX, and a WD Raptor.
Seem low? It should. But not because it's inaccurate, it's because everyone sees the huge Power Supply numbers being put out by the PSU companies, and they think that they must immediately have a 700W or 850W Power Supply.
Now what kind of a Power Supply would you need to run this system with a 8800GTX? In a perfect world, you would need a Power Supply rated at 273W. Yes, the power supply would have to say [Name of Company] 273W. We can round that up to 300W for simplicity's sake.
But our world is far from perfect. Power Supplies should never be run at 100%, or even near 100% output. A simple example is when you turn your computer on. At that instant, every piece of hardware in your computer goes to it's max power consumption for a couple of seconds as it starts up. This max is higher than what your system shows even at load. So if your PSU can't supply that -- Your computer can't turn on. For example, CD drives draw ~1A from the +5v and +12v rails, and hard drives may get up to 1A on each of those as well. While that may not sound like much, each of those components can more than double that draw on spinup. Thus, if you have too many of either component, you computer may not be able to POST with an inadequate PSU. Also, Power Supplies get hot, and that heat leads to deterioration over time. As if that wasn't enough, you will leave yourself absolutely no room for upgrading. So getting a power supply near the max of your load power consumption: Bad.
Besides that, many other "bad things" can happen to PSUs that would take a few more paragraphs to list. PM me if you want to learn more (and make your eyes bleed from reading). Its normally a good idea to leave a decent amount of breathing room for your PC and some more overhead as PSUs deteriorate over time.
Also, all power supplies are not made equal. While Watts are a nice indication of a Power Supply, it's the Amps that are most important. Especially the amps on the +12v rail.
So...what kind of PSU would be needed to power a system with an 8800GTX? A Forton 400W PSU with 34A on the +12v rails (it has 2 rails) is a good choice. 34A means that it can supply 408W on it's +12v rails, although the actual output is less than the sum of the two rails. But a Power Supply that has more Watts being supplied on it's +12v rails than the entire PSU can is an indication of an EXCELLENT Power Supply. For an 8800GTX system like the one above, this Power Supply would be running at 68% load, and gives you an overhead of almost 50%. It doesn't get much better than that.
Someone disputed that a 550W PSU wouldn't be enough for an 8800GTX system. Fact is, that a 550W PSU would be quite overkill, but I wouldn't argue if someone wanted to get it to leave room open for some [pretty hefty] future upgrade. A 550W PSU would give you an overhead of about 100%.
Hope this will keep people from wasting money on 700W PSUs when their system actually needs less than 250W. Questions are welcome.
Continued
Continued 2
Why Watts Don't Mean Jack
Lets talk about how much power AN ENTIRE 8800GTX SYSTEM consumes.
Clicking on this link will take you to a DailyTech article exploring the 8800GTX. In this review, they will also look at how much power an 8800GTX consumes. Look near the bottom, that's where you will find the power consumption. You will also find these specs;
* Intel Core 2 Extreme QX6700
* NVIDIA nForce 650i SLI based motherboard
* 2x1GB PC2-6400
* NVIDIA GeForce 8800GTX
* Western Digital Raptor 150
Now note this; Incase you didn't read the article, they mention that the power being measured is from the wall, meaning that the actual power supplied to the components is less, after factoring in the PSU efficiency. They are using a Power Supply that has an efficiency rating of 85% (excellent). And incase anyone's curious, they're using a Kill-A-Watt power meter to measure the power that their system's pulling in (again, from the wall).
That means that while they are measuring 321W out of the wall for the entire system, the actual power that the system is pulling in is (321W x .85) = ~273 W. 273W power consumption for a system with a Quad Core processor, high-end motherboard, 2 Gigs of RAM, an 8800GTX, and a WD Raptor.
Seem low? It should. But not because it's inaccurate, it's because everyone sees the huge Power Supply numbers being put out by the PSU companies, and they think that they must immediately have a 700W or 850W Power Supply.
Now what kind of a Power Supply would you need to run this system with a 8800GTX? In a perfect world, you would need a Power Supply rated at 273W. Yes, the power supply would have to say [Name of Company] 273W. We can round that up to 300W for simplicity's sake.
But our world is far from perfect. Power Supplies should never be run at 100%, or even near 100% output. A simple example is when you turn your computer on. At that instant, every piece of hardware in your computer goes to it's max power consumption for a couple of seconds as it starts up. This max is higher than what your system shows even at load. So if your PSU can't supply that -- Your computer can't turn on. For example, CD drives draw ~1A from the +5v and +12v rails, and hard drives may get up to 1A on each of those as well. While that may not sound like much, each of those components can more than double that draw on spinup. Thus, if you have too many of either component, you computer may not be able to POST with an inadequate PSU. Also, Power Supplies get hot, and that heat leads to deterioration over time. As if that wasn't enough, you will leave yourself absolutely no room for upgrading. So getting a power supply near the max of your load power consumption: Bad.
Besides that, many other "bad things" can happen to PSUs that would take a few more paragraphs to list. PM me if you want to learn more (and make your eyes bleed from reading). Its normally a good idea to leave a decent amount of breathing room for your PC and some more overhead as PSUs deteriorate over time.
Also, all power supplies are not made equal. While Watts are a nice indication of a Power Supply, it's the Amps that are most important. Especially the amps on the +12v rail.
So...what kind of PSU would be needed to power a system with an 8800GTX? A Forton 400W PSU with 34A on the +12v rails (it has 2 rails) is a good choice. 34A means that it can supply 408W on it's +12v rails, although the actual output is less than the sum of the two rails. But a Power Supply that has more Watts being supplied on it's +12v rails than the entire PSU can is an indication of an EXCELLENT Power Supply. For an 8800GTX system like the one above, this Power Supply would be running at 68% load, and gives you an overhead of almost 50%. It doesn't get much better than that.
Someone disputed that a 550W PSU wouldn't be enough for an 8800GTX system. Fact is, that a 550W PSU would be quite overkill, but I wouldn't argue if someone wanted to get it to leave room open for some [pretty hefty] future upgrade. A 550W PSU would give you an overhead of about 100%.
Hope this will keep people from wasting money on 700W PSUs when their system actually needs less than 250W. Questions are welcome.
Continued
Continued 2
Why Watts Don't Mean Jack