Originally Posted by blackbalt89
I just tried pulling 900 core for the Metro Benchmark and ended up hard resetting the PC. I have no idea why though. I've read in many places that 850w is more than enough to cover OC'ing two 580s and a full case of fans and the likes.
I also read that the HX-850 for short periods of time can safely pull much more than the sticker says it can. Just how much are these cards pulling?
I have limited choices when it comes to power supplies due to wanting to retain the bottom intake fan on my HAF 932 which is only compatible with PSUs not longer than 7.09".
Does anyone know if a full shutdown of the PC while benching is a sign of too much load on the PSU or is something else getting a bit wonky here? Phaedrus says that 850w is more than enough. :/
Even with both of my 580's at 900MHz and 1.1V, it never went past something like 810W power draw measured at the wall, while running Crysis benchmark or 3DMark 11. After efficiency of 90% is taken into consideration, I was looking at around 730W being drawn from the actual components. Therefore, an HX-850 is more than capable to handle what you're throwing at it. The issues you are looking at stem from an unstable OC as subz3ro mentioned.
Going back to the screw driver you needed for the backplates, the latest revisions of the 500 series cards don't seem to be using Torx screws anymore. When I installed the backplates on my cards, I was all set to use the same Husky Torx screw driver I bought from Lowe's (which I used last time on my 570's), only to be disheartened to find out they switched to regular small screws.
Fortunately, this has started to come in handy for other uses, but that's a different story altogether.
With that said, I think you will find very minimal differences when switching out the TIM. EVGA supposedly uses a semi-low grade version of Shin-Etsu. Back when I had the 570's, I changed one of the cards out with the "higher grade" Shin-Etsu I bought from Microcenter, and was surprised to I find no difference whatsoever - maybe 1C difference, but certainly not enough to warrant the work put in to make it happen.
Unfortunately, if heat is an issue, you really only have several options:
- Don't overclock.
- Let it go and just deal with it, as the temps are still OK up to the mid 90's.
- Flash to the fanspeed unlocker and let the fans howl.
- Put in some aftermarket cooling (air or water).
- Change to a different motherboard that allows better slot spacing.
Sadly, SLI is just the gift that keeps on giving, lol!