overpowering a psu
- Thread starter Yanko693
- Start date
The power consumption depends on demand placed on a supply not simply because a supply is larger then the next. When there's no demand there's also no current flow. The load you place on a supply is what places the call for power. The larger the load the more amps(width of current flow) are pulled.
houseofbugs
New Member
Nope. BUt your efficiency will go down as the unit wont be running @ full capacity.
~Tim
~Tim
Okedokey
Well-Known Member
Efficiency plummets when a PSU is running at 100%. Good PSU's however will have an efficiency curve of around 80% or more between 60% and 90% load. Some even at 100%.
A good heavy supply is generally preferred since it does leave extra on a custom build especially for things like upgrades, additional devices, and of course the rush to oc by many. You can place a good heavy load on a larger reliable not cheap made supply and it won't even wince. Get a wimpy psu and add a drive to see that pulled down fast.
You can calculate the exact wattage needed all day for a specific system. But not leaving room for later expansion or some new video card, SLI or Crossfire setup, etc. is often seen.
A 1500w supply? Even a 1000w model tends to be a bit overkill even for ocers. A basic build generally sees a 450-500w supply while a gaming rig will see an average of 500w upto some new 850w model for those ocing cards as well as memory and cpus.
You can calculate the exact wattage needed all day for a specific system. But not leaving room for later expansion or some new video card, SLI or Crossfire setup, etc. is often seen.
A 1500w supply? Even a 1000w model tends to be a bit overkill even for ocers. A basic build generally sees a 450-500w supply while a gaming rig will see an average of 500w upto some new 850w model for those ocing cards as well as memory and cpus.
Okedokey
Well-Known Member
It has very little to do with wattage. I have seen 750W psus with only 2 x 20 A rails and a quality 550W PSU with the same or more amperage.
You want the following:
ATX 2.2 and EPS 2.91 cert.
Active PFC
80+ efficiency
polymer capacitors
ball bearing fans
MTBF rated at 40oC not 25oC
26A on the 12V rail total (if EPS) or minus 12V+1 if not
5 year warranty
preferable single rail 12V.
You want the following:
ATX 2.2 and EPS 2.91 cert.
Active PFC
80+ efficiency
polymer capacitors
ball bearing fans
MTBF rated at 40oC not 25oC
26A on the 12V rail total (if EPS) or minus 12V+1 if not
5 year warranty
preferable single rail 12V.
As mentioned earlier it depends on the load and what a supply can handle not how large a number wattage wise. The load of hardwares/devices is what places the demand for power on a supply.
For a basic or budget build you won't need to 20a or more on the rails while most better made supplies generally see 18a there. If you have a gaming rig in mind with a high end card the bare minimum however is 450w up depending on what else you toss in like extra drives and devices.
The sticky on supplies is one thing you may want to look over for ideas and the good/bad list of makes and models in general. http://www.computerforum.com/computer-cases-power-supplies-cooling/announcements.html
A system that requires a 200w or220w supply is generally a prebuild with energy saving in mind while a single HD and optical drive build with a half way decent video card(not top model) and even sound card will work well with a good 420-500w supply in. For plans on later expansion and perhaps using the same supply on the next build the investment then would go towards a heftier model to be prepared in that sense.
For a basic or budget build you won't need to 20a or more on the rails while most better made supplies generally see 18a there. If you have a gaming rig in mind with a high end card the bare minimum however is 450w up depending on what else you toss in like extra drives and devices.
The sticky on supplies is one thing you may want to look over for ideas and the good/bad list of makes and models in general. http://www.computerforum.com/computer-cases-power-supplies-cooling/announcements.html
A system that requires a 200w or220w supply is generally a prebuild with energy saving in mind while a single HD and optical drive build with a half way decent video card(not top model) and even sound card will work well with a good 420-500w supply in. For plans on later expansion and perhaps using the same supply on the next build the investment then would go towards a heftier model to be prepared in that sense.
Okedokey
Well-Known Member
This is poor advice. You first say that its not about wattage, then you go on recommend PSUs based on their wattage! WTF??? For an AGP system you need 18A minimum on the 12V rail and for a PCIe system you need 26A.
Factor in the 240VAC limitations of ATX design standard 2.2 and you will see that 12V+1 is dedicated to the CPU, isolating that from the rest of the system. The wattage is meaningless by itself, so please refer to actual specifications. PC Eye show me a 420W PSU that will work with a 8800GTS (oooh and even a sound card) lol?
Factor in the 240VAC limitations of ATX design standard 2.2 and you will see that 12V+1 is dedicated to the CPU, isolating that from the rest of the system. The wattage is meaningless by itself, so please refer to actual specifications. PC Eye show me a 420W PSU that will work with a 8800GTS (oooh and even a sound card) lol?
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Apparently you don't read too well. If you reread the last post you will note what is seen in parentheses about "not a top model". As for AGP cards I;ve run older builds here where there was only 15a or 16a seen on the rails with the older 350w and 400w supplies.
As for the sticky on supplies you will have to take that up with someone else there. But I'm sure you will get put in place rather fast.
As for the sticky on supplies you will have to take that up with someone else there. But I'm sure you will get put in place rather fast.
Gee? I wonder how that old 300w Antec managed to power that old NVidia card some years back? A 350w model seeing 16a on the single rail powered an ATI Radeon 9550 256mb AGP without a hitch.
An 8800 and an older AGP card like a 9550 are two totally different items to consider. And I never stated it was the "top" model but no low ender either.
An 8800 and an older AGP card like a 9550 are two totally different items to consider. And I never stated it was the "top" model but no low ender either.
PC eye, that all fine and dandy. At one time I had a old socket A with a Athlon XP 2400 and a AGP 9800pro running on a 350 watt single rail of only 16 amps. And it ran fine. But I only had one 40 gig harddrive/one cd burner with onboard sound and lan. If I have hooked up another harddrive or used a bunch of PCI cards it would have probably not even booted.
Running a system like that your always right on the line of under the minimum standards. You never recommend or suggest someone to run a system that way. Plus the efficency of the P/S goes down the tubes that way.
For most getting into any new build at this time wouldn't even be looking at an AGP but PCI-E 1.1 if not already deciding on which 2.0 card to go with. You'll also note board manufacturers "recommend" a 350 what? a 350w supply minimum for a stripped down system.
The general advise I usually pass on is to look for slightly over what is optimum to allow for later expansion as far as supplies are concerned. Even on the last build here that saw an AGP card a 430w supply was in. The last of 939 builds saw a 480w then 550w go into that.
You can review what was seen while swapping supplies for another type of reference regarding not seeing a new supply work at first. http://www.computerforum.com/80790-bad-board-simply-need-replug.html
Your the one that brought up AGP cards running on a old computer with a 350 watt P/S (big deal) trying defending yourself by suggesting a borderline power requirements.
Plus what in the world does that thread have to do with this thread? I,m really confused what screwed up pins in your power connectors have to do with P/S requirements.
But of course I'll get 2 paragraphs on how screwed up power connectors-old computers-AGP cards and how you think the Mississippi river runs backwards has to do with this thread.
Plus what in the world does that thread have to do with this thread? I,m really confused what screwed up pins in your power connectors have to do with P/S requirements.
But of course I'll get 2 paragraphs on how screwed up power connectors-old computers-AGP cards and how you think the Mississippi river runs backwards has to do with this thread.
jdbennet
New Member
yeah i used to run a geforce FX 5950 on 18a in a machibe a number of years ago. Formerley it had 15a and it had problems. 18a is reccomended for a high end AGP system, but 15/16a can run a lower end AGP system fine.
On older AGP systems (pre pentium 4) there tended to be much more emphasis on the 5v etc... instead of the 12v
On older AGP systems (pre pentium 4) there tended to be much more emphasis on the 5v etc... instead of the 12v
Okedokey
Well-Known Member
The funny thing here PC Eye, is you have yet to refer to anything other than wattage. As i have said, wattage alone is meaningless when it comes to a PSU's ability to adequetely power a system.
Yanko, a PSU will only deliver the required current that it can within its specifications, meaning you can attach a 1KW PSU, but it will only draw what is required from it.
Yanko, a PSU will only deliver the required current that it can within its specifications, meaning you can attach a 1KW PSU, but it will only draw what is required from it.
Current drawn depends on the load placed. And I was mentioning before "manufacturers's recommendations" for the atx minimum is 350w. Or can you comprehend that? bigfella
Yanko693 The newer high end PCI-E card will see the additional power feed just like boards since the Pentium 4s and all newer Intel and AMD socket types see the additional 4wire 12v cpu feed due to the larger vpu chips. It's more or less seeing a second cpu taking the load off of the main processor to see work done there.
That's a larger load placed on a supply drawing more amps. You'll commonly see the 450w minimum recommended simply due to the larger wattage supplies tend to also provide more amps on rails as well as the additional power connections.
That also applies easily to drives as well since a 700w supply will likely see 6 sata power connectors while a 450w may only see 2. When putting together any higher end performance build you will be looking at the specifications seen on the supply as well as all other hardwares.
Yanko693 The newer high end PCI-E card will see the additional power feed just like boards since the Pentium 4s and all newer Intel and AMD socket types see the additional 4wire 12v cpu feed due to the larger vpu chips. It's more or less seeing a second cpu taking the load off of the main processor to see work done there.
That's a larger load placed on a supply drawing more amps. You'll commonly see the 450w minimum recommended simply due to the larger wattage supplies tend to also provide more amps on rails as well as the additional power connections.
That also applies easily to drives as well since a 700w supply will likely see 6 sata power connectors while a 450w may only see 2. When putting together any higher end performance build you will be looking at the specifications seen on the supply as well as all other hardwares.
Okedokey
Well-Known Member
Anyone can read a manufacturers recommendations, that doesn't mean that on a forum like this it is useful or wise to pass on that recommendation without qualification, that was simply what i was saying. Those of us who know what we are talking about should qualify such statements with actual specificiations (qualities) when recommending someone a PSU that only has 350W, as it will very very rarely be sufficient for any system these days. BTW, can you show me a reference for this:
not that i don't believe you, just interested. And yes, i can comprehend technology quite well PC Eye.
not that i don't believe you, just interested. And yes, i can comprehend technology quite well PC Eye.