GPU Trouble: Too Hot To Handle
The GT60 Dominator Pro features Nvidia's top-end GTX 880M graphics processor -- essentially a full-sized Kepler GK104 with slightly less memory bandwidth (160GB/s here versus 192GB/s on the GTX 680 and 224GB/s on the GTX 770).
Unfortunately, MSI's cooling solution on the GT60 hasn't evolved to keep pace with the GTX 880M's higher thermal output. The problem doesn't necessarily show up in short benchmark runs, but under sustained load the Dominator Pro can't always exhaust enough heat to compensate for the GPU core. We updated the drivers to Nvidia's latest version available during testing (337.50), but still had problems in sustained gaming.
Here's an example of Metro Last Light frame rates gathered from the benchmark's own utility. The three charts below correspond to the first, third, and sixth consecutive benchmark runs.
Metro Last Ligh: First run
Metro Last Light: Third run. Note the dips and troughs, even though the average frame rate is almost identical (43 fps in Run 1, 41 fps in Run 3).
Sixth Run - Elapsed Time: ~20 minutes
The good news is that most games don't show this dramatic of a slowdown. The drop-off tends to be gentler in most titles, but it does exist in other games. Nvidia's own thermal throttle kicks in as the GPU breaks the 90C barrier, hauling the frequency down to protect the long-term health of the entire system.
Extended play sessions with BioShock Infinite and Left 4 Dead 2 showed performance falling off by 10-15% over a prolonged period of time. But considering that we're testing this laptop in a room with an ambient air temperature of 67F on hardwood and fully dusted, this is as close to an ideal situation as you get in the real world -- and this system can't keep the GPU cool enough to run at full speed.
Unlike the Alienware 17, which can actually sit in your lap during gaming sessions, the bottom of the MSI GT60 gets hot, and nearly burns even through jeans, and it's much louder than the larger Alienware.
We took our findings to MSI and were told that this qualifies as expected behavior, even in cases like Metro Last Light. That's fundamentally problematic given that even at full volume, the laptop can't keep some games from throttling.
A 10-20% performance hit might not seem very large, but that's typically the difference between a top-end and second-best GPU. At the top of the component stack, that's several hundred dollars worth of GPU performance you essentially don't get because MSI hasn't designed a robust cooling solution for its laptop.
If you're wondering why the MSI Dominator Pro GT60 has this problem, it's not hard to see the issue. Here's the bottom of the 17-inch Alienware:
And then, for comparison, the bottom of the MSI GT60:
There's a lot less vent space there, even allowing for the difference in total area -- and we suspect it makes a significant difference.
There is a possible solution to this problem that you can implement without buying additional cooling hardware. If you choose graphics settings that would allow the game to run at 90-120 fps, then lock the frame rate to 60 fps by activating V-Sync, the GPU's power consumption will drop accordingly (see our section on Battery Boost for more information on how battery life and frame rates are related to each other.)
This trick will only work if you pick settings that give the card headroom in the first place. If a game only runs at 30 fps, turning on V-Sync won't reduce heat generation at all.