# Gigabyte motherboard turns on then back off



## markNine (Jul 8, 2010)

Hi there, nice to meet you all.

I consider myself pretty tech-savvy but i'm a little stumped here. I'm building a new computer using parts purchased online or at the store.

These are some of the components i have purchased and am attempting to put together:
Gigabyte H55M-USB3 (LGA 1156 / H55 / DDR3)
Intel Core i5 750 (Quad-core 2.66 Ghz)
Patriot 1GB x2 DDR3 PC1333 RAM
Cooler Master eXtreme Power Plus (600W)
NVidia 8500 GT
+HDD, DVD Drive, etc.

The HDD, DVD drive, and front USB ports have _not_ been connected. The NVidia card is, since the i5 does not have onboard video. I do not have a speaker connected to the motherboard.

I previously purchased a Asus motherboard (coupled with an Core i3 processor) and the same RAM. The computer would boot, stay turned on for 5 seconds, then turn off. The process would repeat itself until i hit the power switch on the back of the PSU. No video.
I had several people tell me it's the motherboard and not the processor, so i exchanged it for the Gigabyte Mobo.

Now my problem is almost eerily similar. The computer boots, fans spin (weakly), the BIOS splash screen appears, key strokes do not register, 10 seconds later the computer shuts off. The process repeats itself.

I've tried booting with one stick of RAM (alternating) and the results are the same. I've also tried different PSUs and i've correctly applied the thermal paste between the CPU and heatsink.

What could the problem be? Are both RAM sticks bad? Or did I pick up another dud motherboard? CPU?


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## Wrench97 (May 10, 2008)

Try doing the bench test, do not skip any steps> Bench Test


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## markNine (Jul 8, 2010)

Hi, thanks for replying.

Problem persists even though the board is on top of the motherboard box and everything is properly connected. 

The post screen appears when the RAM is installed and the computer turns off after around 8 seconds, then turns itself back on and repeats the same process.

There are 4 LED lights (2 Greens, 1 yellow, 1 red) on the motherboard called "Phase LED". They all light up and stay lit until the computer restarts.
All of them are lit up


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## Wrench97 (May 10, 2008)

What is the specific part number of the ram?


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## markNine (Jul 8, 2010)

Patriot PDC32G1333ELK


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## Wrench97 (May 10, 2008)

The ram was designed to run on the P35/P45/X48 chipsets not the P/H55> http://static.compusa.com/pdf/Patriot-PDC32G1333ELK-datasheet.pdf

Also see the image below Patriot does not list any compatible ram for your motherboard.

I assume you have tried clearing the CMOS?


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