Overclocking Issue (P5Q SE Plus)

Hi folks,

When I try to overclock on my new motherboard, I get a strange symptom. I turn off the PC afterward, turn off the PSU at the back, push the power butter to drain the stored power on the board, and then turn the PSU back on. I leave it a moment, and then hit the power button. Essentially I'm trying to recreate a scenario where I have the PC plugged out when I'm not in and then go to turn it back on. Normally it's not a hassle. But, I normally haven't been overclocking.

My overclock is only on the CPU, going from 3.0GHz stock to 3.6GHz. I am leaving the RAM clock at its default. The E8400 is well able for that amount of overclocking, with no or little voltage increase. Plenty of people are able to get it passed 4.0GHz! Mine has E0 stepping so it's a good one. I checked all my settings and tried several a various combination of settings as a method of eliminating what might be causing the problem. I found nothing.


The problem:

OK, so I recreate the plugged out scenario and when I turn the PC back on, the BIOS doesn't post. Rather it spins everything up, the power LED comes on for a second, turns off automatically before anything kicks in (it's all very quick), and then turns on again automatically. After that it boots up as normal, but it's still quite a worrying problem.


My overclocking settings:

Ai Overclock Tuner (default is Auto): Manual
--FSB Frequency (default is Auto): 400MHz
--PCI-E Frequency (default is Auto): 100MHz

FSB Strap to Northbridge (default is Auto): 400MHz

DRAM Frequency (default is Auto): DDR2-800MHz

DRAM Timings: (default is Auto): 5-5-5-18

CPU Frequency (default is Auto, VID is 1.25): 1.25v

DRAM Frequency (default is Auto, vendor recommends 1.9v for it is XMS2): 1.9v

CPU Spectrum Spread (default is Auto): Disabled

PCI-E Spectrum Spread (default is Auto): Disabled


Disabling C1E or SpeedStep made no difference whatsoever, so I put them back on. Everything else inside of the Ai Tweaker in the BIOS is set to Auto. I don't know what manual settings should be applied to certain other voltages and timings, so I'm not going to gamble on it without first knowing more. Increasing the Vcore to 1.275 didn't make a difference either. The only thing that does it setting the FSB Frequency and PCI-E Frequency (bundled settings) back to Auto, along with setting the FSB Strap to Northbridge back to Auto. Keeping the RAM timings set manually at 5-5-5-18 and the same manually set voltages for the CPU and RAM does not cause any issue when the FSB clock speeds are set at Auto (default).

Also, temperatures are not an issue. They are absolutely fine with or without the overclock. Since the Vcore is ~ the same as at stock, there is little difference.


My Specifications are as follows:
[B]
CPU:[/B] Intel Core 2 Duo E8400 @ 3.00GHz
[B]Motherboard:[/B] ASUS P5Q SE Plus
[B]Memory:[/B] Corsair TWIN2X4096-6400C5C DDR2-6400 4096MB CL5 (2 x 2048MB modules running in Dual-Channel mode)
[B]Graphics Card:[/B] Gainward ATI HD4850 512MB GDDR3 VRAM "Golden Sample"
[B]Hard Drive 1:[/B] Samsung SpinPoint F1 1TB SATA2 (32MB Buffer)
[B]Hard Drive 2:[/B] Western Digital Caviar 500GB ATA-100 (16MB Buffer)
[B]Hard Drive 3:[/B] Western Digital Caviar 500GB ATA-100 (16MB Buffer)
[B]Sound Card 1:[/B] Creative Soundblaster Audigy 2ZS Platinum Pro PCI (with an External I/O Module)
[B]Sound Card 2:[/B] Yamaha DSP-Factory DS2416 Studio PCI (with the 5.25" AX-44 Breakout Box)
[B]ADAT Interface:[/B] Yamaha AX16AT PCI Digital Optical I/O Card (linked with the DS2416 and AX-44)
[B]Speakers:[/B] Creative I-Trigue 3300 2.1
[B]Audio Monitors:[/B] M-Audio Studiophile AV 40
[B]Headset:[/B] Creative HS-600
[B]Mouse:[/B] Logitech G5 USB Laser
[B]Keyboard:[/B] Logitech Y-BH52 PS/2 Media
[B]VDU:[/B] LG Flatron L1917S 19" LCD Monitor
[B]Optical Drive:[/B] LG Super Multi DVD±RW SATA-150 Burner
[B]Scanner:[/B] Xerox 2400 Series
[B]Chassis:[/B] Thermaltake Tsunami Dream Series Case
[B]PSU:[/B] Corsair TX650W 650 Watt
[B]Aftermarket Cooling:[/B] Scythe S-FLEX 120mm 1200RPM Case Fans (x2)



Does anyone have any ideas? Reading around has led me to certain advice given that the power switch is faulty, a grounding issue, or the PSU is unable to cope. I don't see how any can apply to me, so I'm at a loss!



Thanks folks.