Dell Precision M6500 exhibiting pink letters during pre-boot assessment test build 4123. When the system boots into windows, the problem is unnoticeable. Seems isolated to post and CMOS related functions. Any ideas? If it were a dying graphics card, would it exhibit in windows? In depth hardware test comes back fine.
Have you more than one stick of ram you could try taking the ram out and using one stick at a time to see if it's a ram issue? They may have even become loose or may not be making proper contact as the laptop warms up metal expands then contact is made this could also be the case for other metal components in you laptop. If you boot the laptop in a warm state and the post boot fault still occurs then you may have another issue.