Overclocking

Intel's control panel offers a good range of overclocking options—no third party software required. Unlike the first generation, Alchemist, memory overclocking is fully supported on Battlemage now, and you can also tweak the voltage-frequency curve.

Unfortunately, there are still a lot of issues in the OC section of the control panel. For example, when changing memory frequency, you have to go in small steps, or the card will crash. While this works as long as you keep it in mind, things fall apart once your card crashes during OC testing. Now Intel's software will apply the last memory OC, as one big jump, which crashes the card right after booting into Windows. There is no mechanism that detects this kind of crash and applies defaults, so you'll be stuck in a loop of manual reboots. The only solution that worked for me, was to switch to a non-Intel graphics card, uninstall the Intel GPU drivers, go back to the B580, install Intel drivers with clean installation settings.

Another gotcha is that increasing the voltage—which is nice to have—will crash the card at some point, no idea why. This shouldn't happen at all. The "0" to "100" range on the voltage limit is also confusing—just give us mV.

What's also important to know is that having the control panel Window open will eat some performance. In my testing, around 3% (44.6 FPS vs 43.3 FPS), so make sure to close it every time you're running a benchmark.

Eventually I gave up on overclocking, because it took forever to swap cards and reinstall the drivers after every single crash. Here's my notes (for the Intel B580 reference card)

• Stock performance 3DMark GT1: 44.5 FPS
• power limit set to max: 44.8 FPS -> just tiny gains
• voltage +30 = 44.7 FPS
• voltage +60 = 44.7 FPS
• voltage +80 = 44.7 FPS
• -> just more voltage = no extra perf
• voltage +90 = crash -> but why?
• voltage +60 & max power = crash
• voltage +20 & max power = 45.6 FPS
• voltage +30 & max power = 45.8 FPS
• voltage +40 & max power = 45.9 FPS
• voltage +50 & max power = 46.1 FPS
• voltage +60 & max power = 46.3 FPS (no crash this time?)
• voltage +70 & max power = 46.3 FPS
• -> voltage and power does help, but only small gains, like 4%
• voltage +50 & max power & +100 MHz clock offset = crash
• voltage +50 & max power & +50 MHz = 46.5 FPS
• voltage +50 & max power & + 75 MHz = 46.7 FPS
• voltage +25 (lowered) & max power & +75 MHz = 46.41 FPS -> as expected, still tiny differences
• max power +50 voltage +75 MHz + 20 GHz mem = 47.4 FPS
• max power +50 voltage +75 MHz + 21 GHz mem = 47.7
• max power +50 voltage +75 MHz + 21.5 GHz mem = crash
• -> Tiny gains from mem OC, like +2%
• mem crash loop ... giving up
• Overall OC is like 44.5 FPS vs 47.7 FPS = 7.2%