Random rebooting while rendering

[Vilandra]

I have a machine that I use for animation, modeling, editing, etc. The hardware is....

Dual Intel Core2 Quads QX9775's
4 Gigs FBDIMM RAAM
Intel D5400XS mainboard
nVidia Quadro FX 1700
Silverstone 1000w PSU
Asetek closed loop liquid cooling

While rendering out animations, the machine will reboot. I dont get a blue screen, or any errors. The 3D application just freezes for a second, then the machine reboots.

Clock speed is 4.0Ghz (CPU multiplier is at 10)

Now heres the weird part.... If I take out the 2nd and 4th RAM sticks (leaving the 1st and 3rd), the system does not reboot. Everything works just fine.

If I have all 4 RAM sticks in, I have to take the CPU multiplier down to 9, and enable the half-ratio option in order to work around the rebooting problem.

I replaced all 4 RAM sticks with new ones, but the problem is still there. For the time being, im going to install two 2gb DIMMS to avoid the problem until I get it resolved.

Any ideas as to what would cause this? Could it be a faulty mainboard or CPU?

Thanks

 

[mpilchfamily]

Well obviosly your OC isn't stable. Have you tried to bump up the RAm voltage yet? Chances are thats all that is needed to get all 4 DIMMS stable.

 

[Vilandra]

Yes. I took the DDR and AMB voltage up, but that didnt work either.

 

[mpilchfamily]

Well the first thing that came to mind was drivers tillyou mentioned that it ran fine on 2 DIMMS. Next item would be trying to tweak the RAM settings more to see if that helps. May be time to play with those timings.

 

[Modelworks]

Which renderer are you using ?
Are you using any plugins with the renderer ?
I have run across a few plugins that crash every pc when used in combination with each other if you even look at the pc wrong while it renders.

 

[Vilandra]

I am using the standard Cinema 4D rendering engine. I have also tried other render engines (other 3D apps) as well, and I have the same problem.

 

[Matt1970]

Reboot the system. Hit F8 and select "Disable Reboot on System Failure" That way you can tell exactly what is giving you the problem.

 

[Vilandra]

I'll give that a try... but I did already disable that using the right click on My Computer --> advanced tab --> startup and recovery method. Im using XP.

 

[Vilandra]

Its been a while since I last updated this situation...

I sent the machine in for repair and they replaced both CPU's. According to them, both CPU's has a faulty core. The RAM was fine.

After using the machine for a couple of months, it started randomly rebooting again while under a load. It would work just fine while checking e-mail, browsing the web, etc. But as soon as all 8 cores hit 100% usage, it could take 5 seconds, or 5 minutes... but it would reboot. No BSOD, no error messages. It would freeze for 3 seconds, then go black and reboot.

I spoke to technical support and we adjusted some memory voltage settings, but that didnt do anything. I also replaced the RAM with new DIMM's and that didnt do anything either.

The only way to work around the problem was the bring the clock speed down to 3.8Ghz. (multiplier at 9, and half ratio enabled). The system is stable now and there hasnt been any trouble.

What would cause this issue with only a small bump in speed? From 3.8 to 4.0 doesnt sound like much, but I guess that must be the stability threshold in that range.