Large enough power supply for this CPU/GPU?

I was going to build an AMD box, but Micro Center has an i5 2500k for $160, and since that is lower-power than an AMD... I thought I could save some money on the power supply and have it go to the processor!

CPU i5 2500K
Cooler Coolermaster 212
Motherboard ASRock Z77 Pro 3
Memory DDR3-1600 Corsair 8GB
Graphics Gigabyte 7770
Hard drive 1TB Seagate
Case Corsair 300R
Power supply Earthwatts 380, 350, or Corsair CX430
DVD drive Sony

Cost after rebates, without Windows: $632

I know the 7770 is going to be the bottleneck, but it's 80W, compared to the 150W GTX 560SE, or the more powerful Radeon 6850 (127 W). So, compared to either, I can get by with a 50-70 Watt lower power supply. Plus, my current monitor only supports 1680X1050, it should give me great FPS at that resolution.

Likewise, the i5 2500k is lower power than the AMD units, and I probably won't go too wild with overclocking, maybe just pushing it to 4 GHz with no additional voltage. Well, I suppose at some point I'll have to see if I can push it to 4.4. or 4.5 GHz with extra voltage, but I don't think I'll run it that hard in general. Heck, It'll be much faster than my current single-core AMD even at stock speeds! But, I can't help but tweek some...

Micro Center doesn't have the Earthwatts 380, they have a 350!! Is that enough for me with an overclocked 2500K and a 7770? I see Tom's has a 2500k build with a 650-watt power supply and dual video cards, just one of which takes more power than the 7770.,3027.html

That's 166 watts at CPU load, 214 overclocked... 387 cpu/GPU load, 486 overclocked. Take out one of those GTX 460s, and reduce the power of the other to 7770-level... what size power supply do I need? 430? 380? even 350? I don't anticipate 2 video cards, ever, so I don't need excess capacity. And, I don't want to pay $100 for a 650 watt power supply when I can get away for less than half of that.... maybe! But, I don't want to use a 350 watt power supply where a 450 one is required. I like the Antec supplies, because I think they are solid, but the Corsair 430 has me worried. They are rated at a lower temp level, and my room doesn't have AC, so it does get into the 80's during the summer. Otherwise, that looks like a good (but inexpensive) power supply.

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  1. Best answer
    A system with an HD 7770 needs a recommended 430 watts. That assumes a generic, low quality unit so you could get by with the Antec EA380. The Corsair 430 CX is one of the better budget power supplies on the market though. I have used it in quite a few builds and never had a problem with one. It would be my choice just based on quality although the Antec units are fine.

    PSU requirement list.

    The 430CX is only $35 at newegg.
  2. Pfft! The best laid plans... things have changed, although it all worked out.

    My wife came along to put in her 2 cents about cases, and she was OK with the Corsair Storm Enforcer (I thought she might think it too "styled" and want something blander, like the 300R), and the salesperson convinced her that I needed a bigger PSU. So, rather than a 600CX, I wound up getting an Antec Earthwatts 500D. That should be fine! I would have preferred an Antec somewhere between 380 and 500, but they only had the Antec 350 (??) and 500. I thought the 350 might be a bit underpowered, but is 380 that much better? I'm sure the 500 will be able to handle it with no problems!

    And, to boot, he said that he would give me $50 off if I went with an i5 3570k instead of the 2500k... which made the combo $20 cheaper. Faster, newer, cheaper? I'm all over that!

    All the rest stayed the same. I'm going to go build now... Thanks for the advice, even though I didn't heed it!

  3. Best answer selected by enobiko.
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