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Help finding PSU

I recently purchased a Nvidia 250 gts graphics card. When I tested it out my computer will rarely but sometimes will turn off to "prevent Hardware damage." Im almost certain it is the PSU b/c my echo star 650 only has 22a on 12v rail, and the gpu requires 24. Im trying to decide on a power supply but am confused about my requirements for the other rails on my system.
My specs:
Windows 7 64-bit
AMD Athlon X4 2.6ghz
8gb ddr2
MSI gts 250
1TB 5400RPM hard drive
CD/DVD combo drive
Any help is greatly appreciated and would this likely work?
http://www.newegg.com/Product/Product.aspx?Item=N82E16817341019&nm_mc=EMC-SW052410&cm_mmc=EMC-SW052410-_-index-_-PSU-_-17341019-L0D

Thanks
9 answers Last reply Best Answer
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  1. msday94 said:
    ...the gpu requires 24.
    That 24Amp recommendation is for the entire system - not just the video card.
    So a PSU that can deliver 24Amps of +12V power would work in your system.
    I think you're exactly right that the Echo Star 650 is at the root of your problem.

    A really good deal right now is the CORSAIR 400CX with 30Amps of +12V power $60 before $20 rebate and another 10% during the NewEgg sale. And free shipping.
  2. WR2 said:
    That 24Amp recommendation is for the entire system - not just the video card.
    So a PSU that can deliver 24Amps of +12V power would work in your system.
    I think you're exactly right that the Echo Star 650 is at the root of your problem.

    A really good deal right now is the CORSAIR 400CX with 30Amps of +12V power $60 before $20 rebate and another 10% during the NewEgg sale. And free shipping.



    Then what are all the other rails (+3v, +5v etc.) for? Thanks as u can tell i dont understand a whole lot.
  3. +1 for Corsair 400CX. Its a very nice, reliable and silent power supply :)

    Most of the components powered by your PSU draw power from the 12V rail. So it is the most important. You don't need to look for amps on the other rails.
  4. Best answer
    The rails are basically well regulated transformers that convert domestic current into the voltages that your PC can use. In other words, the PSUs convert the conventional 110V or 220V alternating voltage from the power grid into continuous voltage used by the PC electronic components, which are +3,3V, +5V and +12V.
    Power (Watts) is a factor between current (I) and voltage (V) (P = I x V). If, for example, the transistor is operating at 12 V, the maximum power provided by the Corsair CX400 would be 288 W (12 V x 24 A).
    Anyway, the semiconductors and the inductors have a physical effect calling "de-rating" and because of it they lose their capacity to deliver power with temperature, therefore a maximum power measured at a low temperature may not be reached when temperature is higher. The manufacturers of quality PSUs guarantee that their PSUs can deliver their labeled power at 40°C to 50°C, so those PSUs will deliver their labeled power under a real world scenario and not only at the manufacturer lab. This is an important aspect to consider when we want to buy a PSU.
    About the power distribution, nowadays a typical PC pulls more power from the +12 V outputs because the microprocessor and the graphic card, which are the two most power hunger components from the PC, are connected to the + 12 V outputs (apart of the hard drives, optical drives, some fans, etc which are connected to it too). And that's why, as shubham1401 has said before, the 12V outputs are the most important ones. Nowadays the 3,3V and 5V outputs are responsible for the mobo, memory, expansion cards,...
    If you see that a PSU can deliver more power from its +5 V and +3.3 V outputs than from its +12 V outputs, it means that the design of that PSU is outdated. Some years ago the power distribution was different and the PSUs was maded in order to work properly with that hardware.

    That said, I recommend you to go for one of the following PSUs:

    Antec EarthWatts 500W (EA500-EC) (by Delta Electronics)
    Corsair VX450 (by Seasonic) (the CX400 is enough for your system, but paying a few more bucks you will have a better PSU with more power if needed in a future).
    Seasonic S12II bronze 520W
    Enermax Eco80+ II 500W
  5. Some typical 3.3V and 5V usage:
    + 5V is used by USB devices, Firewire, PS2 mouse and keyboard, PCI slot devices, HDD and DVD drives as well as the motherboard.
    +3.3V is used by the onboard IGP video, the motherboard and various electronic chips.
    A lot of devices use more than one voltage. A HDD/DVD drive can use 5V for the electronics and 12V for the platter spin motor and read/write heads. A PCI sound card or network card is probably using 5V and 3.3V. Motherboards use all 3 input voltages and can transform it into other voltages as needed by other devices. RAM voltage can vary from 1.3V to 3.3V for example.
    SATA power cables offer all 3 voltages to let the SATA devices draw what ever voltages they need. Molex power cables just offer 5V and 12V.
  6. Henry Chinaski said:
    The rails are basically well regulated transformers that convert domestic current into the voltages that your PC can use. In other words, the PSUs convert the conventional 110V or 220V alternating voltage from the power grid into continuous voltage used by the PC electronic components, which are +3,3V, +5V and +12V.
    Power (Watts) is a factor between current (I) and voltage (V) (P = I x V). If, for example, the transistor is operating at 12 V, the maximum power provided by the Corsair CX400 would be 288 W (12 V x 24 A).
    Anyway, the semiconductors and the inductors have a physical effect calling "de-rating" and because of it they lose their capacity to deliver power with temperature, therefore a maximum power measured at a low temperature may not be reached when temperature is higher. The manufacturers of quality PSUs guarantee that their PSUs can deliver their labeled power at 40°C to 50°C, so those PSUs will deliver their labeled power under a real world scenario and not only at the manufacturer lab. This is an important aspect to consider when we want to buy a PSU.
    About the power distribution, nowadays a typical PC pulls more power from the +12 V outputs because the microprocessor and the graphic card, which are the two most power hunger components from the PC, are connected to the + 12 V outputs (apart of the hard drives, optical drives, some fans, etc which are connected to it too). And that's why, as shubham1401 has said before, the 12V outputs are the most important ones. Nowadays the 3,3V and 5V outputs are responsible for the mobo, memory, expansion cards,...
    If you see that a PSU can deliver more power from its +5 V and +3.3 V outputs than from its +12 V outputs, it means that the design of that PSU is outdated. Some years ago the power distribution was different and the PSUs was maded in order to work properly with that hardware.

    That said, I recommend you to go for one of the following PSUs:

    Antec EarthWatts 500W (EA500-EC) (by Delta Electronics)
    Corsair VX450 (by Seasonic) (the CX400 is enough for your system, but paying a few more bucks you will have a better PSU with more power if needed in a future).
    Seasonic S12II bronze 520W
    Enermax Eco80+ II 500W


    You said the cx400 only has 24amps on 12v when it has 30 amps which is the most powerful 400 watt unit you can buy. So CX400 with 30 amps 12 x 30 = 360 watts of power on the 12 v which is quite impressive for a 400 watt unit and for the OP is the unit I would recommend he gets the most, it would serve him well.
  7. +1 @ SAAIELLO
    You can find some 500W PSUs that can't match the Corsair 400CX 30Amps +12V.
  8. Yes, my bad. It has 30A (360W). Thanks.
    Anyway I was just giving an example for my explanation.

    The Corsair CX400W is an excellent product for a system with just one video card, and, as I have already written, It's enough for his system. Anyway, taking into account the price difference, I would go for the VX450 because of its better quality, warranty and power.
    The less amount of transistors used on the primary is the main difference between Corsair CX400W and the Corsair VX450. Moreover, VX450W uses Japanese electrolytic capacitors on the secondary.
    Another important difference is the lower value filtering cap: 270uF @ 400V versus the VX450W's 330uF @ 400V.
    Although the CX's idle/load noise is still quite low, it's higher than the VX's one.
    5 years warranty for the VX. "Only" 3 for the CX.
    Anyway, If he finally decides to save some dollars and buy the CX, he will be buying a rock solid power supply. But in my opinion, there are some better choices for a few more bucks.
  9. Best answer selected by msday94.
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