Is there by chance a CD/DVD in the optical drive? Possible reason for unusual startup is when there's attached usb drive/external harddisk and optical drive and the system is set to detect from external sources before the internal harddisk during startup, thus leading to slower startup.
Flickering of the screen may be there's some slightly loose connection of the display ribbon internally. Have it checked by the technician, although it's not a big issue, but to prevent a surprise when one day you startup your system, finding it without any display (despite it still actually fine).
Laptop: Sony VAIO VGN-FS680/W
When I power up my laptop instead of the usual Sony and Windows startup screen, the screen is gray. After a minute or so the screen starts to flicker and eventually returns to normal. Sometimes I can hear something that sounds similar to gears churning faster and faster when the screen begins to flicker.
This happens on a regular basis. It has not from my opinion affected the performance of the computer. Is this something I should worry about later on?

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