Overheating is the safest guess.

Next time you're forced to Hard Reboot, go into your computer's BIOS, and check the hardware's temperature. If it's over 70 degrees on anything, you're in trouble.

If thats not the case, then check your Power Unit, and make sure it's above 750 watts, because with a setup like yours, you're going to need an powerful power unit.

Other than that, your hard lock ups could be caused by any number of things. You could have easily incorrectly installed SLi support, updated to drivers that aren't compatible with SLi...

70 degrees??? you do know that most cpu's normally operates in the range of about 100 to 120 degrees. My liquid cooled desktop that i put about 8000 dollars into operates at a consistant 96 degrees for the cpu. my case is usually arount 72 degrees. In order to keep anything computer wise under 70 degrees you pretty much need to be sitting in a refrigerator.


unless you meant 70 degress celcius not farhanheit, then we are talking about a different story.

Stop sniveling for one damn moment and listen.

Currently there is an bug with nvidia cards in SLI, especially with vista.

The future 17x.xx drivers will fix it, but right now they are just leaked ones and not even available for vista64.

There is two things you can do. The best is to simply turn sli off when you begin to play sins like I currently do. No big deal and it won't crash.

Or you can turn effects down, specifically off the "highest" setting. That will lower the amount of times you crash but will still happen.

Celsius is typically used when referring to component temperatures.

Ever considered it may also be in part due to your operating system? Vista64 has fairly lousy drivers regardless of the component manufacturer. There just isn't much support and development time being spent on those drivers. Unlike the 32-bit editions.
I'm guessing you need a 64-bit OS for your work or something, because there is no way you need that 8 GB RAM while gaming, even at completely ridiculous resolutions with that SLI setup.

4GB RAM and those cards on 32-bit Vista would probably run anything you want like a dream.

3.25 in my case, 3.5 in the case of anyone with a 512MB card, and 3.75 in the case of anyone with a 256 MB card, etc etc. Your using (roughly) X gigabytes of ram, where X is (4GB - VideoCardMemory). You can occasionally loose memory to stuff like sound cards, if its a really expensive sound card with on board memory.



There is a difference between quality drivers, and simply having a driver. He's implying they lack quality, not that they don't exist.



Actually, several recently released programs don't run on 64 yet (and many more older pieces of software). Why? Because game and software companies aren't going to make the leap until end users make the leap, and end users aren't going to make the leap until the software companies make the leap. Eventually a number of companies will be simply unable to program their software within the 2GB limit of XP, and jump to requiring 64 bit -- at which point the end users will scream bloody murder, and some (but not many) will jump. That will start the tidal wave as company after company jumps, triggering yet more users to jump.

Its going to take a while, however.

As Ron was so kind to point out, i was indeed implying quality rather than availability. Sure the drivers are there, but the consumers get the short end of the development stick. Hardware requiring 64-bit drivers for professional application will undoubtedly work flawlessly, but since so few consumers use a 64-bit OS, i doubt much time is spent developing drivers for consumer hardware. (unless its a Mac, since the latest version is only available in the 64-bit version)

There's a good reason that professional grade graphicscards are in the $4000+ range and not like the consumer version around the $500 mark. When drivers for professionals fail, they tend to either not spend money at that company again or sue the crap out of those responsible for loss of income. The average joe consumer however just whines on some forums and maybe gets a new relatively cheap piece of hardware/software and continues as normal.

Unless the complaint is brought forth in huge numbers a company like nVidia couldn't care less about its normal customers. Even if those people then choose to go to the competition next time they purchase. The money has been made already afteral.

In the past versions of windows there were indeed a difference in quality between 32 and 64 bit drivers, but I'm just not seeing it nowadays for Vista. Microsoft is pouring more support into vista64 than they have ever done in the past. I won't argue that you won't be able to find some poor quality driver made by an unreliable small company that is significantly worse than their 32 bit driver, but it's more and more rare. I've extensively used both vista 32 and vista 64 drivers on two different machines and I have yet to encounter a difference in quality.

I'd be curious to know whether you have had personal poor experiences with vista 64 drivers and what those problems were. Please respond even for curiousity sake.

Also, vista 64 natively runs 32 applications. Long gone are the days when it was a much slower 32 bit emulation. Again, I'd like you to point out a relavent application that can't be run in a 64 bit OS.

I'm not argueing here that Vista is necessarily better than XP, I'm merely stating that telling anyone to go vista32 is bad advice. Vista32 Premium is a massive ram hog, and it doesn't recognize 4g+ of ram. If you have less than 4gigs of ram and do serious gaming you are much better with XP. If you have 4gigs of ram or more and want to run vista 64 is the way to go without a doubt.

Older 64 OS's had driver problems, but it is purely a myth in terms of Vista 64. I'd appreciate if anyone could prove me wrong on the points I have raised.

That's easy to say.

If both your COH game and your Sins game crash on a regular basis, you might blame your computer instead : what's so wrong with it that those two games both crash ?

  

I have Microsoft's Windows XP, and none of my games crash*. Isn't that strange ?!

* The last time Sins crashed was when I had an early beta version -- 8 months ago.

Alway, post your specs and I may be able to help. I've spent some time troubleshooting both CoH and Sins.

No crashes for me so far in Vista. Make sure you have all MS patches installed.

Like other people here have said, it's most likely either overheat or patches.