Alienware's M18x, Part 1: NVIDIA's GeForce GTX 580M in SLI

Heat, Noise, and Battery Life

Now we get to the fun part. Alienware uses muxes to allow you to switch the dedicated GPUs off completely in the M18x (and AMD-equipped M17x R3s), but our NVIDIA GeForce GTX 580M-equipped M17x R3 gets to leverage Optimus. Our net result? Gaming notebooks that can be used for non-gaming tasks off the mains.

Unfortunately, all is not sunshine and roses in the land of M18x switchable graphics. As we discussed in our Dynamic Switchable Graphics article, the use of muxed graphics switching means things aren't as seamless, as you have to wait for the discrete GPUs to power off, the drivers unload, and then the Intel drivers load. All of this takes about 15 seconds, but there's a bright side to the Alienware implementation: even with muxed switchable graphics, the M18x is still part of NVIDIA's Verde Driver program, so you can get up-to-date drivers regardless. You still lose out on Optimus' dynamic switching with SLI notebooks (for now?), but at least you can still get good battery life and up-to-date drivers. Check out the battery life results:

Optimus may still have some teething problems from time to time, but they're rare, and the benefits are undeniable. Meanwhile, the M18x's switchable graphics mean that despite being a 12 pound land monster, you can still take it to Starbucks and check up on your e-mail or watch a movie during a massive flight layover if you're so inclined. Of course, Toshiba's lighter Qosmio X775 winds up really stealing the show, offering nearly as much battery life on just half the battery.

We have our two sets of thermal results side-by-side, with the single GPU enabled on the left and SLI enabled on the right. You can see that having SLI enabled generates enough heat to push the overclocked i7-2920XM just a little bit too toasty, although the surface temperatures of the M18x remained relatively comfortable. Noise levels also increased noticeably in SLI mode, commensurate with the second GPU pulling its weight and thus increasing substantially the amount of heat being generated. Component temperatures remain reasonably low outside of the CPU getting such a good workout, and actually the M18x does keep these two high-end GPUs remarkably cool. End users may want to back down ever so slightly on the overclock.

Subjectively (sorry, my equipment and location isn't good for testing noise levels), the M18x still feels quieter than the Clevo X7200, but an M17x R3 under load is quieter still. Alienware's cooling system in the M18x is remarkably efficient given how much heat it has to remove.