Radeon HD 4290 Overclocking
Nearly every mainboard based on AMD's integrated graphics chipsets permit to overclock the integrated graphics core. And the two mainboards we are discussing here are no exception. You will find the options necessary to set the graphics core clock rate in their BIOS Setup. As our experiments suggest, the Radeon HD 4290 can indeed be overclocked well enough. If you additionally increase the voltage on the chipset's North Bridge, you can achieve a nearly 50% increase in terms of GPU clock rate.
For example, when we increased the voltage on the AMD 890GX North Bridge by a mere 0.1 V above the default value, the integrated graphics core was stable at 1 GHz, which was 33% higher than the default frequency of 700 MHz. This result is not so unexpected, though. Mainboards based on the AMD 785G chipset are about as good at overclocking the integrated graphics core. For example, the one of the Gigabyte MA785GT-UD3H mainboard we use for the sake of comparison was quite stable at a clock rate of 950 MHz with the same voltage.
However, the AMD 890GX-based mainboards we are discussing here can overclock not only the graphics core but also the frequency of the Sideport memory. This option is available in their BIOS. When the voltage on this chip of DDR3-1333 SDRAM was increased to 1.7 V, we managed to raise its frequency up to 1670 MHz on the ASUS M4A89GTD PRO/USB3 and up to 1640 MHz on the Gigabyte 890GPA-UD3H.
This overclocking boosts performance in games by about 25%, which is quite rewarding. The diagrams below show the performance of the platforms when both the CPU and the integrated GPU were overclocked. It must be noted that the GPU overclocking has no effect on CPU overclocking, so the frequency of the Athlon II X4 635 processor in these tests is the same as in the CPU overclocking experiments described in the previous section.
As you can see, the number of frames per second is more or less acceptable in today's popular games (at the lowest graphics quality settings, of course).