680 sc sig OC on SR-2

[bongholio]

hope someone here can help me out...

i am trying to run 3dm11 on a tri-sli evga gtx680 sc sig in an SR-2 with 2x5680's. cpu's, chipset, rams, and gpu's under water.

my problem is when i clocked the cpu at 4.7GHz, where the 680's are +150/+300, TDP@+130% and max voltage is also set in precision-x at 1175mV, it will stop on either the 3rd or 4th test(no signal on monitor).

running at stock gpu clocks has no problem(cpu still at 4.7GHz, 1.57v)

weird thing is, at 4.5GHz the 680's can pass 3dm11 at same oc settings of +150/+300.

am i missing something here? or is my psu (strider 1500W) not providing enough juice to the gpu's when the cpu is already at 4.7GHz? heat is not an issue as the load temps on the gpu does not go above 52C while CPU temps max out at 79C.

note that extra pci-e 6pin is already connected.

please let me know if you need more info. here are some values that might be relevant:

4.7 GHz, 188x25, 1.57v
IOH: 1.4v
VTT: 1.375V
VDIMM: 1.63V (1880MHz, 7-8-7-20)

[Hellshealer]

i would be putting a second PSU on and seeing if would help

[k|ngp|n]

Interesting, so adding 200mhz to you cpu speed causes 3dmark to crash or hard lock using same gpu clocks? When u say no monitor, u mean system is still running and just loses monitor signal or it freezes and becomes unstable?
Does numlock still work when this happens? Did u try switching the dvi port on the card?

[bongholio]

Interesting, so adding 200mhz to you cpu speed causes 3dmark to crash or hard lock using same gpu clocks? When u say no monitor, u mean system is still running and just loses monitor signal or it freezes and becomes unstable?
Does numlock still work when this happens? Did u try switching the dvi port on the card?

yup. going from 4.5 to 4.7 crashes 3dm11... i have a dell u3011 and the signal is lost once the benchmark crashes (screen message says entering power save mode)...

numlock does not respond anymore but the system seems to be running although frozen as i also am not able to toggle from eleet and aida64 on my G19. even if i try to ctrl-alt-del nothing happens so i need to hold the power button to turn system off and restart.

[clare]

Maybe the IOH is faltering somehow from the GPU OC? It's the only thing I can think of related to both the GPU's and increased BCLK.
Have you tried enabling Turbo for a 26x multi? It'll get you 4.7 at 181 BCLK which might make the rest of your system a little happier.