SB system won't wake up when OC @ 4.5GHz

[Meganano]

I've run Prime95 for over an hour several times with no errors, but when I try to wake the system in morning the only sign of life is the front case fan. At this point I have to cold boot.

CPU - Intel Core i5-2500K
MB - ASUS P8P67 PRO
RAM - G.SKILL Ripjaws X Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600
CPU Cooler - Cooler Master Hyper 212 Plus
Video Card- MSI N560GTX-TI Twin Frozr II/OC GeForce GTX 560 Ti
Power Supply- CORSAIR CMPSU-650TX 650W
Hard Disk - SAMSUNG Spinpoint F3 HD103SJ 1TB
Case - Rosewell Challanger (3 fans)

BIOS settings (tell me if you need more)
BCLK 100 MHz
Turbo Ratio 45
Load-Line Calibration Auto
CPU Manual Voltage 1.29

This waking problem doesn't sound like any bad OC symptoms I've heard of, but I've only experienced it when OC'd in excess of 4.0 MHz. I'm thinking I may need to increase the CPU voltage, but I'm already in the pink zone (Asus risk level). Or might setting a high manual Load-Line Calibration solve the problem and perhaps allow me to set the CPU voltage in the yellow range (1.225-1.280 volt)?

 

[Leaps-from-Shadows]

ASUS' risk level doesn't mean anything. The average Sandy Bridge CPU needs 1.3-1.35v to reach full stability at 4.5GHz overclocked speed. You could try different LLC settings though.

As long as you keep the peak Prime95 core temps below 75ºC and the CPU voltage below 1.4v, your Sandy Bridge CPU will last for a good long time while overclocked.

And the waking from sleep problem is pretty common especially with ASUS mainboards. A BIOS fix will be needed to completely eliminate it. In the meantime you can 'fix' the problem by not using sleep mode -- either shut your system down when you're not using it, or use the Power options to put the monitor and hard drive into power-saving mode without actually using Sleep.

 

[Meganano]

Problem solved! Sotiri on the Asus forum suggested I disable Internal PLL Overvoltage. That fixed the problem
http://vip.asus.com/forum/view.aspx?id=20110611021059226&SLanguage=en-us&board_id=1&model=P8P67%20PRO&page=1

 

[Meganano]

I have a pet peeve with people and organizations that send e-mails refusing to accept replies. Why can't I or someone on another forum provide the BEST answer?

Tom, the answer I'd select as Best was not posted here but at the following,
http://vip.asus.com/forum/view.asp [...] PRO&page=1


"Hello ,
your thread "SB system won't wake up when OC @ 4.5GHz" has received some answers. We invite you to review these, and select the best one as your “Best Answer” (click on the gold cup above it).
Click here to review the answers to your question: http://www.tomshardware.com/forum//forum2.php?config=tomshardwareus.inc&cat=29&post=267041&page=1&p=1
Selecting a "Best Answer" will help the community to easily spot answers to similar issues or questions.
Thank you for contributing the Tom's Hardware community
The Tom's Hardware community team"

My reply was the following undeliverable message,

You've only given me one choice and it's not the one I'd pick

 

[Leaps-from-Shadows]

PM a mod and they can choose a Best Answer for you. I would do it, but I only have mod privileges in the Motherboards & Memory forum.

The reason you can't choose a Best Answer other than mine in this thread is you're not supposed to be able to choose your own posts. Like I said, a mod can choose your post as the Best Answer for you.

 

[Meganano]

I can't award myself first prize? So much for answering one's own question
"PM a mod"?

 

[Leaps-from-Shadows]

Yes, there are moderators like mrface and tecmo34 who can do pretty much anything on the forums because they have special access privileges. If you PM (Private Message) one of them through the forums and give them a link to this thread they can choose the Best Answer you want. In case you didn't know, there is a link called "Send/Read Private Messages" at the bottom of the main Forums page. If you have private messages waiting, it will instead read "You have X new messages" or something like that.

I only have special access (moderator) privileges in the Motherboards & Memory forum, or I'd choose the Best Answer you want for you.