I Downloaded recommended Intel® Graphics Driver for Windows* [15.33] for my DELL Latitude E6430, Intel® Core™ i7-3520M CPU @ 2.90GHz BUT I got a message that my "my computer isn't compactable with the version"
Contact Dell for support on your laptop. You should be using the dell supplied modified/customized drivers instead of the intel generic driver. This is especially the case if you have dual graphics.
Yea, if you had the version with the (optional) NVIDIA 5400 graphics, then you need to stick with the drivers that Dell provided. If you only have Intel graphics, you might be able to install the newer driver from Intel (by uninstalling the existing driver, rebooting and then installing the Intel standard driver), but you need to check with Dell if this is supported.