Legit Reviews checked out the AMD 690G chipset and decided to overclock its integrated graphics chip and write an article about it with benchmarks to show how much performance you can gain by doing this.
Their conclusion is that the graphics chip of AMD 690G has plenty of overclocking room, but you shouldn't expect miracles from it of course. They got a 20% performance increase in the game Company of Heroes at 1024 x 768, but the actual FPS only went from 12.7 frames per second to 15.2. In F.E.A.R. they went from 35FPS to 39FPS.
After clicking 'Find Max Core' the system shot from 400MHz well over 500MHz and I was greeted with a nice blue screen of death. After I rebooted and started ATITool, I was amazed that the AMD 690G chipset was able to reach 563.25MHz before the system crashed. I manually set the core clock frequency to 525MHz as anything over 550MHz would cause artifacts and that's not good. Slowly increase the clock frequency 5-15MHz at a time and run game tests to make sure it's stable and not showing any artifacts. Overclocking is an art and takes time to reach, so remember patience is vital.