4pin PSU - 8pin motherboard - fails to POST - Foxconn 946GZ7MA-8KS2H

boxil

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Jan 23, 2009
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I am having a bit of trouble booting up my first homebuilt computer. I'm building an entry level system for general office work:

intel Celeron Dual Core E1400 2.0Ghz
Foxconn 946GZ7MA-8KS2H Motherboard (LGA775, Intel GMA 3000 integrated graphics)
Single stick 1Gb PC2-5300 667mhz Ram
DVD+RW, 40Gb HDD.
ASUS SFX mATX 250W PSU (1x 24pin, 1x 4pin, 4x molex, 1x fdd, 1x sata)

I built it altogether and the system won't POST. No beeps, no signal to monitor. However the machine does power up and I can see all the lights and fans come on. The DVD+RW opens too. I've tried to boot up the system out of the case, in case the brass stand-offs might be shorting something. Still, no result. I've tried to boot up whilst having just the minimal components (CPU, cooler, motherboard, PSU, Ram), and no success either. Thermal paste/cooler, correct wire connections have all been checked numerous times.
I tested each one of the components above separately on my current working machine and narrowed down the problem to the motherboard. However I am not yet sure whether the board is actually faulty, I have other suspicions:

Foxconn 946GZ7MA-8KS2H motherboard takes a 24pin and an 8pin power supply. However, both the ASUS PSU and my working machine's PSU have a 24pin and a 4pin supply. The Foxconn manual "strongly recommends" me to use an 8pin - but states that a 4pin can be used if I really have to - I just need to stick it in the top half of the 8pin. However the motherboard fails to POST.
Unfortunately I don't have a 4pin-to-8pin converter so I can't tell whether this is a power problem or not. I have read in numerous forums that the 4pin would normally work on an 8pin. If that was true then it would definitely mean that my motherboard is faulty. However I was wondering if there are certain motherboards that actually can't take a 4pin? I would be very grateful for your expertise.

The manual is here:
http://www.foxconnchannel.com/support/downloads.aspx?ProductModel=946GZ7MA-8KS2H&TypeID=en-us0000001
 

merlinbadman

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Jul 19, 2007
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The P4 should work fine by itself, just make sure you are plugging it into the corrct half of the 8-pin socket (the bit with the small wedge so it clips), usually the bit nearest the top of the case.
 

boxil

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Jan 23, 2009
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Yep, the PSU's 4-pin says 13A, +12Vb. Together with the 24pin (9A, +12Va), it says 180W is supplied, which should be more than enough.
Also, I've made sure to stick the 4pin in the correct half (in fact it only fits in that half). I also bought a 4pin to 8pin converter and tried that - but still no luck.

I guess the motherboard is faulty then. I've returned it to the sellers, and when they test it and do find it faulty, I will be able to get a replacement. In fact the sellers said the 4pin should have worked.

Thanks for your advice.