Asus Sabertooth 990FX R2.0 boots twice....

Hi all,

Maybe one of you guys can help me out here are my specs: (its a new build btw)

Asus Sabertooth 990FX R2.0 MB (latest bios)
Corsair TX850 PSU
XFX R7 250 Core Edition Passive GPU
Kingston KHX 1600C9D3K4/8GX 1.65V (4 x 2 GB) RAM
Samsung 840 EVO 120GB SSD
Intel 40GB SSD

Cpu, vrm and nb are all costum watercooled with a XSPC RX480 rad. Temps Idle cpu = 25c to 28c at full load p95 its 52c my vrm idles at around 24c to 28c at p95 its 53c nb stays pretty much at 33c to 35c. So cooling should be good enough.

System = default setting no OC.

Whenever I turn on my pc cold boot) it boots fine NO error led warnings nor error sound warnings I enter w7 desktop and 2 to 3 sec later it reboots after that I can use my pc without issues. Now im also using dual boot on a seperate ssd with Linux Ubuntu 12.04 LTS the same happens when im at the desktop as with reboots. So looking at windows event viewer is kind of mute now since it happens with ubuntu as well (and I erased the w7 ssd)

I have no clue what is going on...this is what I have done so far:

Removed the w7 ssd and just use my ubuntu ssd no change...
Reinstalled W7 and nothing changed...
Reinstalled Ubuntu 12.04 LTS and nothing changed...
Used Memtest for 7 hours and nothing changed...(no errors).
I did a CMOS reset no change...
Updated my BIOS to the latest succesfully but no change...
I chose to use D.O.C.P. in order to let my ram run at its native speed (9-9-9-27) no change...
Ive removed 2 out of 4 ram modules to see if the problem insists which it does...

Should I manually set the ram timings if yes how please know im using 4 x 2gb modules, im not realy into OC'ing the cpu, only want to change the ram timings to its correct spec if needed otherwise its default setting at 1333mhz.

Some say its normal that asus motherboards boot twice BUT is it normal to reboot while you already are at the w7 or ubuntu desktop for approx 2 or 3 sec? Thing is after the second boot I can do whatever thing I want to no problems as of yet...when i used W7 i did not had any BSOD's.
Some say to up the vcore a bit slightly increase the voltage but my cpu is already factory OC thats why I bought it so I wouldnt have to fiddle with the bios settings....

Hopefully some one can help me, it seriously drives me nuts.

Thanks in advance.
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  1. I think i solved the issue, so maybe people in the future can see this IF they have the same problem like i did.

    What i have done included the above trial and error is as follows:

    I swapped my graphics card with one that i know is working 100% i booted up so far so good till i got in ubuntu desktop (no doubt this would happen also with w7 desktop) and it rebooted, very dissapointing i had only one option left since prime95 and memtest went well. So i changed my psu from a TX850 version 1 to a HX650 watt psu i was little worried because of the 650 watt since the FX-9590 is rated at 220watt but i guessed it was only for booting up and not stress testing.

    I detached all the psu cables to my MB (tripple check) and hooked up my HX650 psu outside the case tripple checked everything was connected. Fingers crossed and i started the pc up....went to ubuntu desktop i expected a reboot which to my surprise did not came i waited and waited guess im lucky i then did a hard reset and booted ONCE no reboot. I then turned of the pc and psu, removed the psu cable from the wall and hooked up everything back up again booted again and no double boot!!! So i gues i either had a faulty psu OR a psu that was not compatible with my MB and cpu.

    All whats left is i need to buy a new 850 psu my choice would be a Corsair RM850 watt.
  2. The RM series power supplies are poorly made and have cheap capacitors.
  3. Best answer
    Made by the best = SEASONIC.

    PCPartPicker part list / Price breakdown by merchant / Benchmarks

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  4. RM Series Ltec capacitors used throughout <-----poor capacitors.
  5. Ok thanks for the replies,

    Can you guys give a list of verified excellent brands of psu (850 watt range) ive been using a Corsair AX850 in my main gamerig so far so good no issues "knocking on wood"
    Is the AX760 any good does it use top of the line components/capacitors?

    All i need is a psu that is compatible with the asus sabertooth 990fx r.20 since it could be that my TX850 was simply not compatible with my mb or faulty...

    Share your recomendations peronaly im looking at the Corsair AX760 since that one is easy to get..

  6. sorry for the late reply. HX series are solid units. the AX uses Sanyo OS-Con polymer capacitors and Rubycon electrolytic capacitors and Nippon Chemi-Con electrolytic capacitors.

    the AX series are solid units.
  7. @ModernWarfare

    Thanks for the recommendations and information. I know now what to get.
  8. good luck :)
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