Hopefully a mistake in your BIOS, because the Memory Check is very early in the process.
Look in the BIOS for anything different from past settings (if you remember what they were!) The manual might give you a list of default settings.
Look for memory check on/off, also for any strange video settings, because it wont go far if these are not what the computer expects.
After, or perhaps before that, it would be wise to look for loose cards and connecting leads.