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EPS12V questions. (max current per wire? 18AWG? is Y-splitter safe?)

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LeetMiniWheat
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2010/08/25 02:47:26 (permalink)

So I just got a new shinny CORSAIR Professional Series AX850 850W ATX12V v2.31 / EPS12V v2.92 80 PLUS GOLD Certified Modular Active PFC Power Supply (I know I grossly overpaid at $189.99)

To my dismay, when using all 4 PCI-E power plugs you can't use the 2nd EPS12V wire. (Limited to two PCI-E with both EPS12V) Yeah, thanks Corsair. Might have been nice to mention this?

I've heard it said many times that both wires are not necessary, HOWEVER I have a few questions still:

1. How much power can a single EPS12V (8-pin) wire draw? I've heard the classy can draw a max of 600w with both plugs, does this mean a single plug carries 300w? That sounds dangerously close if a single 4ghz i7 can draw between 200w-300w.

2. Even if I'm not drawing the max from the wire, would there be any voltage drop compared to using two dedicated wires? Would it put any additional strain on the classified's PWM's with one plug empty? (I'd imagine having more routes to suck power from would give it an easier job)

3. Is 18AWG wire thicker than normal? How many amps/watts can be carried through it without voltage drop or burning up, etc? I'm pretty sure my Corsair PSU has an 18AWG EPS12V

4. Would a Y-Splitter help any? I have dilusions that somehow with a thick enough wire (18awg?) that it'll still be able to draw more power from both plugs, and the motherboard's traces on either side would be filled more evenly. (I bought one of these EPS12V Y-Splitter )

Thanks for any replies, this just really bothers me seeing an open plug on my motherboard. That, and not getting a feature I paid for in this power supply.

CPU: Core i7 4790k + Water     Mobo: Asus Maximus VII Hero
GPU: EVGA GTX TITAN X         RAM: 32GB (4 x 8GB) 2400MHz (G.Skill RipjawsZ)
SND: Sound Blaster Z                   PSU: EVGA SuperNOVA 850 G2
Case: Lian-Li Armorsuit (PC-P50R)  Monitor: Acer XB270HU 1440P G-Sync  
Keyboard: Corsair Vengeance K70 Mouse: Logitech G700 
Storage: 128GB SSD (Samsung 830) | 2TB Raid0 (2x Samsung F3) | 1.5TB (Samsung F3EG)
Speakers: Harman/Kardon AVR-145 | Klipsch Quintet IV 5.0 Satellites | Lava 12" 250w Sub
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    KMoore4318
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    Re:EPS12V questions. (max current per wire? 18AWG? is Y-splitter safe?) 2010/08/25 06:32:42 (permalink)
    Don't worry about the 2nd 12V plug ( unless your phase change cooling or Liq Nitrogen, and OCing in the 5.0 range. a single plug can provide about twice the power you need for a good 4.0 ranged OC, ( about 180 Watts. )

    A typical 8 pin is 28 amps 336 watts or there about. The second plug is only for those extream OCers.

      
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    LeetMiniWheat
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    Re:EPS12V questions. (max current per wire? 18AWG? is Y-splitter safe?) 2010/08/25 13:59:19 (permalink)
    Thank you.

    1. Is that 28amp/336watt on 20AWG? or 18AWG?

    2. 180 Watts for a 4.0cpu? hmm, maybe my numbers were off. even on high volts, i.e. 1.35v-1.4v?

    3. so there won't be any voltage drop with 8 pins instead of 16?

    4. no added strain on the classified PWM's?

    I was reading somewhere that some cheaper PSU's use 20AWG wires. so I'd assume 18AWG can carry more? If so, possibly a Y-Splitter would help ease a higher load between the plugs? I'm still a little worried about a voltage drop of some sort as I creep higher in volts to get a higher OC. (Not happy with 4.0)

    CPU: Core i7 4790k + Water     Mobo: Asus Maximus VII Hero
    GPU: EVGA GTX TITAN X         RAM: 32GB (4 x 8GB) 2400MHz (G.Skill RipjawsZ)
    SND: Sound Blaster Z                   PSU: EVGA SuperNOVA 850 G2
    Case: Lian-Li Armorsuit (PC-P50R)  Monitor: Acer XB270HU 1440P G-Sync  
    Keyboard: Corsair Vengeance K70 Mouse: Logitech G700 
    Storage: 128GB SSD (Samsung 830) | 2TB Raid0 (2x Samsung F3) | 1.5TB (Samsung F3EG)
    Speakers: Harman/Kardon AVR-145 | Klipsch Quintet IV 5.0 Satellites | Lava 12" 250w Sub
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    KMoore4318
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    Re:EPS12V questions. (max current per wire? 18AWG? is Y-splitter safe?) 2010/08/25 15:03:35 (permalink)
    The EPS 12V if for the CPU a I-7 at stock is about 130 watts, OCing it to 4.0 will add about 50 more so your looking at 180 watts, You can handle aboyt 75 watts per yellow and black pair, so an 8 pin is about 300 watts You have more power with a single 8 pin than you will ever need, With wire gage, the smaller the number, the larger the wire, so 18 gage is better than 20, and can carry more amps.
     You can of course find a converter and plug it in through your standard PSU 12V plugs, if you would perfer to have four times what you need, insted of only about twice what you need. the TDP if a Stock I-7 is only 130 watts, a four pin can handle that.

      
    Just clink Link to Register >  My Affiliate Code:VTJPDC4OMB 
    1)965 V-8  E761(77)
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