Intel fixes multi-monitor power issue
It works but not in all instances.
Intel Arc A7 GPUs were known to suffer from high idle power consumption from the very start. The company has provided a guide on how users can achieve lower power states when using Arc GPUs. This may greatly reduce the power consumption (below 10W) for these cards when they are idle.
Unfortunately, even those fixes did not solve an issue with multi-monitor setups. Intel Arc GPUs would simply not hit the lower power states with more than 1 monitor attached. This contributed to relatively high (40-50W) consumption even when the system is idle.
What should be said first is that it is perfectly normal for graphics cards to consume more power when more than 1 monitor is used. Graphics cards simply need a lot more power to feed data to two or three monitors. The higher the resolution and refresh rate, the more likely higher power consumption is to occur. However, two 1080p or even 1440p monitors shouldn’t really require that much power to run.
Intel has been working on a fix for this problem ever since Alchemist was released. Finally, it appears that it has now been at least partially resolved, partially because the system/BIOS changes are still required. That said, if your GPU suffered from high idle power even after implementing Intel’s recommendations, the new driver is unlikely to improve multi-monitor power use.
However, for some users the latest 4146 drivers have shown great results indeed:
Single 2560×1080: 11 W
2560×1080 + 1600×900: 38-40 W
Single 2560×1080: 7-8 W
2560×1080 + 1600×900: 8-9 W
But expectations need to be set right, says an Intel engineer. The Arc GPU will not enter lower power states when 3 or more monitors are used. So keep that in mind.
Source: Intel Issue Tracker