PCIEX16 Not Working GA-Z68XP-UD3

[y2kcompatible]

I submitted the following information to technical support but was wondering if anyone else has come across this issue:

After cold reboot of computer the video no longer displayed.  Found that the video card installed in slot PCIEX16 no longer had power.  I am assuming there was no power since the video card fans were not spinning.  Also, all of the Phase LEDs on the motherboard were lit.  Powered down the system and moved the video card to slot PCIEX8.  The video worked fine after this and the computer booted up properly with no issue.  Also, none of the Phase LEDs were lit.  Powered down and moved the video card back to PCIEX16; retested and the video card did not work again (fans not spinning, no output).  Moved the video card back to PCIEX8, rebooted, and the computer has been working fine for several hours.  So the slot PCIEX16 is now defective due to some unknown issue after a cold boot up.

I've been using all of the same hardware and software for over a year with no issue.  I think the PCIEX16 slot is defective but I'm not sure why it would suddenly fail.  The BIOS version is F7; no changes were made by me but I haven't checked to see if any values were reset on their own.

Any info would be appreciated.

[y2kcompatible]

Now PCIEX8 is not working either.  The phase LEDs are all lit as well.  When the phase LEDs are not lit then the system boots up fine.  The phase LEDs are related to CPU loading according to the manual.

[Fatman]

Can you please tell us what components you are running. For eg what Power supply unit, Video card, motherboard Ram etc and Monitor and how have you connected it. Via HDMI or VGA or DVI ? Then we will have a better understand as how to help you.

[y2kcompatible]

Hello,

I've discovered that I can successfully boot up the computer if the HDD listed below is unplugged right before POST.  This has proven to be a 100% success rate.  However, if I plug in the HDD then the chance for successful boot up is not very good.  The computer may just hang or reboot itself several times (on its own) and then eventually boot up correctly.  This does not always happen; sometimes the computer just hangs and will not boot.

I've tried different power channels on the power supply.  I've tried different combinations and slots for RAM.  I've tried putting the video card in both PCIEX slots.  The chance of a successful boot up is hit or miss.  If I unplug the HDD then it boots every time as stated.

So to get the computer to boot I unplug power to the HDD, press the tower power switch, then immediately plug in the HDD so that the BIOS recognizes.  Once the computer has booted up all of the hardware operates correctly.  The computer has now been on for a couple of weeks with no issues at all.  Even soft reboots recover fine.  The problem is only seen with cold reboots.

Here is some of my hardware info:
MB Model Name : GA-Z68XP-UD3(rev. 1.0)
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VGA Brand : GIGABYTE      Model : GV-N430OC-1GL
CPU Brand : Intel      Model : i5      Speed : 2400 (3.10GHz)
Operation System : Win 7 64-bit      SP : 1
Memory Brand : G-Skill      Type : DDR3
Memory Size : 8Gb      Speed : 1600 PC3 12800
Power Supply : 650 W (PC Power and Cooling)
Monitor: Asus LCD connected through DVI
SSD: Corsair Force 3 60Gb
HDD: Seagate SATA 1TB