The first thing to do is check if Dell has a BIOS upgrade. Our Dell SX270's needed a BIOS upgrade before the onboard intel graphics would work properly. Keep in mind that they are not VESA compliant, so don't expect anything fancy in text mode. Then use the BIOS to increase the memory for the graphics from the default 1MB to 8MB (or whatever your BIOS allows). You should be able to get at least 1024x768.