Advanced patterm test fail WME02-IQ8

Hi

After Dell 2320 started playing up i did the health check and the one at start up (F12) and to start off with it said the MXM fan failed. Not knowing what this was i decided to have a looking in the pc which was very dusty. Found where i believe the MXM fan is, and vacumed the dust of it, which seems to have cured this ?

However, also from the first health check it failed on the Advanced pattern test WME02-IQ8. What is this and how do i fix it.

Thanks