P8Z68 Pro Gen 3 cold boot issue.

Michaeljcox24 · 21 Jan 2012 at 10:34

I updated to bios 0402, enabled power on by PCI-E, but still, I have this intermittent problem where the machine boots, then switches itself off, then reboots itself, then hangs just after the BIOS post screen with a flashing cursor. Happens about 6-7 times a week

Is there still no known solution to this fault or is the board actually faulty?

Michaeljcox24 · 21 Jan 2012 at 13:14

P8Z68 pro gen 3
2500 K @ 4.6 Ghz
P8Z68 Pro Gen 3
8GB Corsair Vengance Black
SLI 580's
Corsair HX1050

Thanks

Michaeljcox24 · 21 Jan 2012 at 13:46

I tested the memory, no faults, and the same thing happened when I booted with the board out of the case with nothing connected. Really annoying, because it doesn't happen every time so it's difficult to nail down.

Michaeljcox24 · 21 Jan 2012 at 13:58

1.1 and 1.5

Michaeljcox24 · 21 Jan 2012 at 16:54

Ok, thanks for the help so far lads,

I'll try

1 - increasing memory voltage to 1.55 volts.
2 - Change the force bios option.
3 - Ensure that SSD is first boot priority (I think it already is but will have to check when I get home)
4 - I do manual overclocking so I don't know if the overclock tuner will make any difference.

Michaeljcox24 · 22 Jan 2012 at 15:21

Have e mailed asus suppport, I changed pll overvolting to auto (which is apparently disabled now) and still had the problem with it this morning. Have not changed memory voltage, that is last resort, but I've changed force bios option.

Have seen loads of posts on other forums listing the same issue as mine, so Asus will know the solution. Either that, or they will tell me my board is knackered lol

Michaeljcox24 · 22 Jan 2012 at 19:35

yeah when asus e mail me back (usually get one in the middle of the night from an chinese tech support lad) I'll repost in the morning with their response. Ram is compatible according to the asus spec sheet, and I've ran super PI, Burn test, and Prime Blend all at the same time with cpu on stock to test it. Usage went up to 99% but not once did it drop out.

My thoughts at the moment are along the cpu needs more voltage for 4.6, 8GB perhaps needs more than 1.5 to get going at that CPU overclock. Unless of course, it's the force bios thing, which is might well be. Don't know. I don't see how something in a rig can work one day and not the next.

Michaeljcox24 · 23 Jan 2012 at 12:46

Asus have asked if i use xmp and to run the rig with one memory module in then get back to them

Michaeljcox24 · 23 Jan 2012 at 13:28

If you google it gigabyte boards do it too which is random

Michaeljcox24 · 23 Jan 2012 at 17:07

Just come in from work and tried to boot the machine up. For anybody who has this board, this is the crucial bit of info that could help solve the problem

I have the Marvel disabled, on board sound disabled, and the JMB disabled, so right after the bios post screen, in the top right hand corner, on a good boot, you get a flashing white cursor, then that dissapears, then you get one slightly below it, then the windows loading screen.

The machine always hangs on the first flashing white cursor, so whatever it is doing then, is causing the problem (one would think)

Current steps:

Have increased memory voltage to 1.55
Set memory timings to cas 8 as rated on the side of the sticks
put PLL voltage back to enabled because it wouldn't even boot at all with it disabled. This was with one stick in at a time aswell.

If it still fails to cold boot tomorrow, will run at stock for a week or so as per recommended by Elevon and see what happens.

Michaeljcox24 · 23 Jan 2012 at 20:03

Latest update. blue screen crash on boot. irq not less or equal

Michaeljcox24 · 23 Jan 2012 at 20:41

Im stumped. run memtest and get no errors.

Michaeljcox24 · 24 Jan 2012 at 07:52

Further Info which may be related:

Last night I had another problem appear which has happened several times before but I'm wondering if the two may be related?

Once the machine had booted (I had speaker on already), the mouse froze up. I could hear from a speakers, I continual noise of the USB being plugged in and out from windows, and almost like it was loosing power and then getting it back (the mouse stayed plugged in throughout).

I'm wondering if the boot problem is related, because boot issues seem to have gotten ten times worse since I upgraded to a new ASUS monitor, which has no USB ports on and forced me to use all 4 usb ports on the back of the board.

Perhaps USB ports are loosing power (or not getting enough power) which is causing lock ups during hardware detection on boot.

EDIT: Just read another thread where one lad showed memtest flagged up dodgy ram caused the issue. Will run tonight with one stick at a time (ive been running with both in at the same time) schoolboy error.

Michaeljcox24 · 24 Jan 2012 at 22:33

May have cracked it. Using xmp the command rate shows up in cpu-id as 2T, and I remember when I first set the rig up, using manual timings the command rate defaults to 1T if you don't change it. At the time I didn't know that Vengeance ram was set to 2T, it's not declared on the side of the stick, so I assumed it was 1T.

Will run for a bit longer, 5 reboots and no locks ups on boot, promising so far.

Michaeljcox24 · 26 Jan 2012 at 11:47

The main problem is the command rate on the board defaults to 1T unless you change it to 2T, which the Vengeance is rated at. The command rate isn't listed on the side of the stick, so I suspect the vast majority of people will assume it doesn't need changing and leave it alone.

It should say 9-9-9-24-2 on the side, would have stopped a hell of a lot of forum posting.

Since getting the command rate at 2T,

- Loss of USB power has stopped happening.
- No more lock ups on boot and double / treble boots.
- 3D benchmarks like heaven are a bit smoother and not jumpy in certain places.
- IE9 no longer locks up and intermittently doesn't load a page with no explanation.

I'm not saying everyones problem is exactly the same as mine, but with an overclocked CPU with would seem on this board, unless you get the timings exactly right, it causes all sorts of problems.

Michaeljcox24 · 26 Jan 2012 at 12:40

If I were you mate:

- Go on the Asus website and find out if the ram is officially supported, in their QVL list for the board

- Go on the Kingston Website and download the datasheet for your set of sticks, it should tell you the timings

- Make sure everything in the bios is set correctly memory wise, this board doesn't seem to like the wrong settings at all.

If your memory is set correctly after all that, try changing loosening it a bit, eg 9-10-9-27-2) (assuming 100% correct is 9-9-9-27-2)

Michaeljcox24 · 27 Jan 2012 at 14:51

I'm still getting the very occasional bad boot at 9-9-9-24 2T, so gonna try one of them as a 10 instead. Seem some ram timed that way for sale on OC

Michaeljcox24 · 28 Jan 2012 at 10:58

dougie180 said:
owner of a Asus P8Z68 VPro/Gen3 and have the same problem.
Im not sure if it is just a coincidence as i have only had the board running 2 days but if i unplug any usb devices before cold boot it seems ok? BTW no overclocking or messing in bios at this stage (std out of the box)

Interesting that you have the same problem at stock.

I have tried upping the memory voltage to 1.55 but the problem still happens.

I might invest in a powered USB hub, i wonder if it would make any difference.

Michaeljcox24 · 28 Jan 2012 at 19:23

Ok....

Early days yet, but I bought a powered USB hub this afternoon, got 4 devices plugged into it (the same number I had into the back of the board)

Just plugged it in, and machine booted first time, with no hang, no double boot at all.

And machine had been off since lunchtime. To early to make conclusive judgement, so will turn off again before I go for a pint and then boot up when I get back in for another check lads.

Michaeljcox24 · 29 Jan 2012 at 00:37

Right...

Might of had a skinfull, but I just booted on the first time, no issues at all, not one single problem.

If I go all week not having a single bad boot, I'll declare to this community the root cause of the problem on this board at the moment bad USB power.