Updating to any driver beyond14.1 beta v1.6 results in crippled performance.
intel driver version 10.18.10.3621 according to device manager (cannot get version according to intel due to how worthless their driver GUI has become)
The performance loss is identical to the Enduro issues encountered on the 12 series drivers over 2 years ago. GPU usage is low for no apparent reason, particularly when running applications that run at higher fps. 14 series driver summary:
14.1 good performance
14.3 poor performance
14.4 good performance on first install. Later reinstalled and had poor performance.
14.7 poor performance
I'm at a loss to why this is happening. I first saw the problem on the 14.3 driver. Rolling back to 14.1 fixed the problem. I later installed 14.4 with no performance issues, but reverted back to 14.1 for other issues that I thought were driver related. Next I attempted the install the 14.7 RC and again had the performance loss issues. Installing 14.4 yeilded no improvement. Going back to 14.1 then fixed the issue. Going from 14.1 to 14.4 again caused the performance loss to return despite this upgrade pattern not causing this problem before.
GPU utilization drop linearly corresponds with performance loss. As previously stated, applications with higher framerates are impacted the most, while those with lower framerates are impacted the least. Ex. 3dmark11 runs at around 50 fps and is virtually unaffected. Diablo 3 runs at around 100 fps (on a good driver) and has a 40% performance loss. Running an old small testing program called ATITool runs at 3400 fps and has a 60% performance loss. I have not tested many games to see more specifically what is and what is not impacted before reverting to the reliable 14.1 driver.
I found it very odd that 14.4 ran properly the first time I tried it, but not the second or third. I do not remember if the 14.4 I first tried was a beta prior to WHQL release or not.
If anyone has any ideas on what's going on I would like to hear them. 14.1 is getting rather old now and the driver's age will soon start causing problems for newer games.