Gigabyte GA-X58A-UD3R rev. 2.0 Boot problem. Reboot and No POST.

[tharun518]

I recently bought a Gigabyte GA-X58A-UD3R motherboard.
The problem is that, on pressing the power button, the motherboard LED light comes on, the fans begin to spin but the motherboard does not post, and there is no display, the motherboard will stay in this state for about 5 secs and then reboot and the same thing happens and this goes on endlessly.

Even after replacement of the motherboard under warranty claim 3 times, the issue has not been resolved. I checked all my components with another motherboard (GA-X58A-UD5) and the system ran with no issues.

My Processor: i7 950
RAM: Corsair XMS3 CMX6GX3M3A1600C9
Graphics Card: MSI nVidia GTX 460 Cyclone 1GB
SMPS: Corsair TX750W

I see many are facing the same issue with this motherboard. I tried solutions in other threads but didn't work.

[Triplefun]

I am having the same problem

I have built a new system using second hand parts - 650W Liam Li PSU; 4 x 3GB 1600Mhz CL9 Kingston Memory kit (1.65v); i7-950 CPU; Nvidea 210 Graphics (I plan to use it as a server with 3 8-way RAID cards). BIOS is from tweaktown F9D. Settings are optimized. I have tried memory profile1 and 'no profile' with manual settings.

When I power the system on it invariably does 5 second recycles with no display or sound other than the fans starting up. Mobo status stays 88.

If I switch the system OFF (cold start) and reload from BIOS (mobo back panel switch), then after 2 and no more than 5 retries it will post successfully.
Once on, it will do an 'instant' restart OK.

If I do a shutdown and wait more than 2 minutes then when I do a start (WARM start)  the system resumes the 4 second restart sequence.

I have had occasional periods of apparent stability but this is shortlived and the system eventually re-enters the POST cycling.

Once operational it will run securely for 48 hours or more. I have run Memtest and Prime45 with no issue.

I have disconnected the USB devices (Logitech wireless keyboard and mouse) with no change.

I thought it may ne memory related since this is what the BIOS 'recovers' from and have tinkered with the recommended settings to no avail
The startup says 1600Mhz; if I am successful the CPUZ say 800Mhz and Windows 400Mhz.
When the system recovers with a BIOS post the startup frequency is sometimes 1033Mhz and sometimes 1600Mhz.

I have replaced the PSU and battery with no success

Is it Mobo or CPU