nesman Posted December 26, 2008 Share Posted December 26, 2008 Well I was wondering if the PSU my case is coming with [450 watts] is enough to run my computer..also I want to know what will happen with a bad PSU. Specs are below.. Link to comment Share on other sites More sharing options...
MaaseyRacer Posted December 27, 2008 Share Posted December 27, 2008 I will probably be fine, however to be safe I would google a proper power supply calculator, this way you can be sure of what your needs are. Also you may want to think of some potential expansion desires as well and see if your current power supply will still work for you. Link to comment Share on other sites More sharing options...
nesman Posted December 27, 2008 Author Share Posted December 27, 2008 Thanks,- I used some PSU calculators and newegg gave the most. The rest were around 300's while Newegg was 575 or so. I hear that the newegg's PSU calculator isn't as accurate as some. Link to comment Share on other sites More sharing options...
LogicalUser Posted December 28, 2008 Share Posted December 28, 2008 wattage alone is a very poor gauge of a power supply's capabilities. a better gauge would be the amperage available between the +12V rails i for one was not impressed by the performance of a cheap 500watt coolermaster PSU, ran very very loud with my E8400, EP45-DS3R and GeForce9800GT replaced with a new Rosewell 650watt PSU i got for an insane deal recently, and its less than 1/3rd the volume, seems cooler as well. many lower priced PSUs well..... they lie about wattage, or provide theoretical peak maximums for their wattage rather than real world maximums or actual continuous load capabilities for example my rosewell 650watt PSU says its max is 750watt peak for 60sec, which makes sense if its able to output 650w continuously. now imagine a PSU that is claiming to be 450watt yet is capable of a steady 300-350 and a 450watt peak for 60sec... yes its 450watt capable, but deceptive, an unfair comparison power supply hardware review sites provide some very useful info, they disassemble a wide range of PSUs and report on the parts inside, their actual capabilities, etc.... was very informative to read about... "oh, this '500 watt PSU' has identical internal components & is manufactured by the same subcontractor as this other '360 watt PSU' from a different brand" http://www.hardwaresecrets.com/ has some informative comparisons as for a bad PSU.. well, a cheap/underpowered PSU would run very hot, and likely very loud when under load as well, with high load & heat, you get increased chance of components inside the PSU failing, shorts, fire, etc... PSU's are often on sale for very heavy discounts, i've seen PSUs on newegg for a fraction of their MSRP, $160 OCZ power supplies with - $70 instant rebate and then a $45 mail in rebate, $120 PSUs for - $40 off and a $40 mail in rebate, hell, the rosewell 650watt PSU i got was on sale for $18 with free shipping, reg price of $100 or so Link to comment Share on other sites More sharing options...
nesman Posted December 28, 2008 Author Share Posted December 28, 2008 Wow thanks a lot, that site has a lot of good info on power supplies. Link to comment Share on other sites More sharing options...
Ankiel Posted December 28, 2008 Share Posted December 28, 2008 I am building a new hackintosh with similar specs to yours. Some differences are that I am going to have another 500 gb harddrive and 8 gb ram. I bought this PSU from newegg yesterday: http://www.newegg.com/Product/Product.aspx...N82E16817341010 It seems to be a very nice one, and with a $25 discount and $30 mail in rebate, it's quite a steal at the moment. Link to comment Share on other sites More sharing options...
LogicalUser Posted December 29, 2008 Share Posted December 29, 2008 i too was looking at that PSU, and would have purchased it had newegg not had a 80% off shell shocker deal on the Rosewell PSUs Link to comment Share on other sites More sharing options...
nesman Posted December 29, 2008 Author Share Posted December 29, 2008 I was looking at the case PSU and heres the specs: 450 watts +12V - 21.0A -12V - .8A -5V - 0.5A +5V - 34.0A +3.3v - 28A Reviews say that the PSU is pretty reliable for a case PSU. However my graphics card recommends a 400watt PSU with a +12V of 25A, would this PSU supply power to my graphics card even though its at 21A?? I can't seem to find a PSU with a higher Amp like in the 20's. Btw my computer parts are ALL coming in tomorrow - WOOT or Oh man...? Link to comment Share on other sites More sharing options...
LogicalUser Posted December 29, 2008 Share Posted December 29, 2008 you are correct, if that is all the PSU provides for +12V that will not be sufficient for your 9800GT in fact, i'm in shock that a "450 watt" power supply can only provide 21A of +12V, seems very low your graphics card recommends +400watt and at least 26A of +12V. what that means is that the COMBINED amperage of the +12V rails needs to be above 26A, not that you need a PSU with 26A of +12V on a single rail. it is uncommon to find a PSU with a single +12V rail above 20A without spending like + $100, normally you get a single rail split to multiple +12V rails, each current limited to something like 12-20A each, and then a combined max amperage figure for +12V as a whole... say for example.... four +12v rails at 20A each, but with a combined max +12v draw of 60A, meaning any one or two of those rails could pull their full 20A, but not all four rails. really, you need a better power supply. now, that said... the one you have now would likely "work", in that your computer would boot, however i would not recommend gaming until you've got a better PSU, as your system is more than capable of overloading that PSU Link to comment Share on other sites More sharing options...
nesman Posted December 29, 2008 Author Share Posted December 29, 2008 I see what you mean. Like the PSU posted before had 4 +12V rails with 18 Amps each. But if one rail needed more power, it would draw power from the other rails to get the full 25, so that rail it drew power from, would run at a lower amp. Seems to sort out the PSU issue I've been dealing with, thanks a lot ! I still have one last worry about my build which would be my CPU. So far I haven't bought any third party cooler as I am planning to use the intel's stock fan and heatsink. Would that be any problem if I don't choose to overclock it? Link to comment Share on other sites More sharing options...
LogicalUser Posted December 29, 2008 Share Posted December 29, 2008 the specified power requirements for your graphics card are NOT for the card itself, they are for your entire system including the card. you do not need 26A on one rail, you need 26A of +12V total, having it split between several rails is just fine. a PSU with two or more 14-18A rails would be fine. that PSU posted earlier with four +12v rails at 18A would provide a total of 72A on the +12V, so more than enough a 9800GT cannot draw anything even close to 400 watts & 26A, but your entire system including the 9800GT would require 400watts and 26A of total +12v capability to run at high loads. much of the total +12V required by your system is going to be for hard drives, fans, etc... or components fed via the ATX 24pin and 4/8pin CPU plugs, which will be provided via a different rail than the PCI-E power for the graphics card. Link to comment Share on other sites More sharing options...
nesman Posted December 29, 2008 Author Share Posted December 29, 2008 Oh I understand now. Your info helps me a lot As for the CPU, would the stock cooler/heatsink be sufficient enough to run without any problems by not overclocking it? Link to comment Share on other sites More sharing options...
LogicalUser Posted December 29, 2008 Share Posted December 29, 2008 yes, the stock cooler/heatsink should be fine for running it at default speeds, its not a "bad" heatsink setup really, just nowhere near as beefy as aftermarket options, much smaller heatsink fins, less efficient at heat distribution, more fan noise, etc.... the biggest complaint with stock intel coolers is the installation, alot of people seem to have issues with the push-pin locking design Link to comment Share on other sites More sharing options...
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