Can only get to BIOS if mem test is run

I purchased an asus sabertooth 990FX motherboard mid last year and it was working great for around six months. However one day it starting doing something really strange that I have been trying to fix for ages. I have exhasted all of my knowledge now so require so help.

The issue is that when I boot up the system will start and the fans will start but before it reaches BIOS the PC will shut down with the DRAM LED lighting up just before. I then push to power on a second time, a mem test is run and I am told Overclocking failed, enter setup. I go into the BIOS and select the Windows Boot Option and the system starts up fine.

I can then use the system perfectly until I need to shut down or restart and the same thing happens again. This means that whenever I turn on my PC I have to go through BIOS just to boot on the second attempt of poewering on after a memtest passes.

If you have any ideas it would be greatly appreciated. I have tried updating BIOS, installing new ram, resetting CMOS, buying an SSD and installing windows there in case the motherboard start up was too fast for the HDD to start spinning (as you can see clutching at straws a little now)

Thanks in advanced

 

I would reset the BIOS (CMOS module) again to ensure you are NOT overclocking. I would also swap in a known good power supply to ensure you are feeding your system good, clean, stable power.

I would also test the RAM as described in my canned text below. If all checks out good, call ASUS tech support to get on record as this could be a motherboard issue. But do this soon as many ASUS motherboards are warrantied for just 1 year now and it sounds like your year may be near run out.

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You can test RAM using one of the following programs. Both require you to create and boot to a bootable floppy disk or CD to run the diagnostics. Allow the diagnostics to run for several passes or even overnight. You should have no reported errors.

Windows Memory Diagnostic - see the easy to follow instructions under Quick Start Information,
or
MemTest86+ (for more advanced users) - an excellent how-to guide is available here,
or
Windows 7 and Windows 8 users can use the built in Windows Memory Diagnostics Tool.​

Note, however, that software based RAM diagnostic tools are good, but not conclusive. So you might try running with just a single RAM module to see if it fails. Repeat process with remaining modules, hopefully identifying the bad stick through a process of elimination.

 

Thanks for the fast reply. I have logged a case with Asus just in case but will try resetting the CMOS again just in case as you suggest.

I will let you know how I get on once I have a chance to run some more checks.

 

Sounds like a plan. Keep us posted.