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Post by BH_Target on Nov 26, 2012 10:06:05 GMT -6
Saw the one above but I'm looking to spend less. And then there's the other problem, size. My case is a micro case and will accomodate a unit 6" deep; 5 9/16-9" long; and 3 9/16" tall. And if you read this VG, I took a look at the vid card this morning. My card is so old that there is no socket to plug a power cord into. That's alright since my existing 450 watt PU doesn't have a 6 pin plug available anyway. I need to finish this build before it snowballs any further. Boy did I get shcooled by the experiance. And I thought I was being smart by buying a barebones kit.
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Post by BH_Target on Nov 26, 2012 10:30:54 GMT -6
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Post by BH von Güber on Nov 26, 2012 10:42:24 GMT -6
I'd see Hawk's comments on Thermaltake... edit: you should also check the amperage requirements of the graphics card you're looking at. The thermaltake you reference only shows 23A on the 12v1 rail...I think my 460 card wanted 32A, but that's relying on memory. It would be worth checking. edit: it takes 24A, as it turns out. Here's a quick read on some things to keep in mind when shopping: compreviews.about.com/od/cases/bb/PSU.htm
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Post by BH_Target on Nov 26, 2012 12:47:50 GMT -6
Good thing my debit card is still afouled. Has kept me from blundering in. VG I'm going to order, as soon as the cash is returned, the card you showed me. www.newegg.com/Product/Product.aspx?Item=N82E16814130841 I looked under details but couldn't find any reference to the amperage the card requires. Could be my man eyes. But how do assertain this vital info?
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Post by BH von Güber on Nov 26, 2012 14:39:02 GMT -6
You'll have to look it up on EVGAs site. They have links for specs on all their cards. Wait, I've got the site open.... www.evga.com/support/specs/
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Post by BH_Target on Nov 26, 2012 14:46:11 GMT -6
I read a min. of 20 amps on the 12 volt rail. OO-rah looks like it'll work. Unless 3+ amps is cutting it too close.
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Post by BH von Güber on Nov 26, 2012 15:02:33 GMT -6
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Post by BH_Target on Nov 26, 2012 15:26:25 GMT -6
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Post by BH von Güber on Nov 26, 2012 21:24:18 GMT -6
I meant by the question mark that I don't know if that was cutting it too close. I suspect it would have been, though. The 80 plus cert is a good idea; 80% of 45 amps is still 36, which is more than enough to run your gpu. Low end supplies are less efficient, generally, and if they were to dip down to 60% or so, bad things could happen. Assuming the efficiency rating works with amps as well as volts, that is...can't remember ohm's law.... The support forums are full of PSU related failures, for what it's worth.
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Post by BH_Target on Nov 27, 2012 11:03:27 GMT -6
Resistance in parallel circuits, OHM's law I4=100div.x100=1amp* I had to look that up, man have I forgotten a boatload. This may not even have any bearring on the topic at hand if the circuits aren't in parallel. But it was a challenge to see if I could still find the answer. And my wife wanted me to throw out all my service courses. *Intermediate Electricity US Coast Guard Institute; Pamphlet No. W22902 (11/83) Gunnersmate course 2nd class.
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Post by Hawkeye on Nov 30, 2012 10:44:45 GMT -6
If a power supply shows that it puts out 45 amps on the +12V rail, it's supposed to put out 45 amps (within the limitations shown on the power supply's chart; most times there is a TOTAL amount of amps that includes other voltage outputs. So the 45 amps might depend on the load of one of more other outputs). 80% efficient would mean that (at least) 80% of the power (measured in Watts) consumed by the power supply from the input line (120 Vac power input) would be available to use at it's outputs. Therefore, if you have a 750 Watt power supply that is 80% efficient, if it was putting out 100% of it's capability, that power supply would actually be consuming almost 950 Watts (or less). The difference between the input and the output are losses inherent to electronics, such as transformer losses. Since energy is neither created nor destroyed, the lost energy is disapated as heat (calories, BTU's whatever). There are 3 formulas to figure power (Watts): Volts times Amps, Volts squared divided by resistance, or Amps squared times resistance. If both of the two variables in any of those formulas are known, you can calculate power in Watts. The units must be whole units on both variables to get an answer in whole Watts. Otherwise, results will be in units depending on what you input. "E" is the variable for Volts. It stands for "Electomotive force". "I" is the variable for Current (Amps). It stands for "Intensity". "R" as we know is resistance, measured in Ohms. (BTW, the reciporical of Ohms is Conductivity, and the unit of measurement for that is "Mho's", which is "Ohms" spelled backward no kidding). Ohm's law: Volts equals Amps times Resistance. Amps equals Volts divided by Resistance. Resistance equals Volts divided by Amps. (The variable Resistance is further subdivided into the sum of pure Resistance, Capacitive Reactance, and Inductive Reactance, and known as "Impedance", symbolized by "Z", for AC circuits. I don't know what the heck you found there, Target, but that formula isn't for resistance in parallel, which really has no bearing on what you guys were talking about. The formula for resistance in parallel is: The reciporical of: (the sum of the reciporicals of all of the parallel resistances). Thus endeth the lesson
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Post by BH_Target on Nov 30, 2012 13:36:00 GMT -6
Yeah, but, will the PU I ordered be enough for the vid. card I also ordered?
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Post by Hawkeye on Dec 1, 2012 9:16:34 GMT -6
Yes it will, if it doesn't happen to fail after 2 hours like in 50% of the reviews currently posted for that power supply.
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Post by BH_Target on Dec 1, 2012 11:09:51 GMT -6
Here's hoping I'm in the 50 percentile.
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