I got a Dell studio 1555. A few weeks ago after a reboot the I could hear the optical drive sound when booting but no monitor output. Gave me the 6 beeps after a bit which I identificed as a video card / motherboard failure.
To my surprise, I tried booting it again a few days later and it worked fine. Kept working fine for a few more days and then would go back to not starting.
I tried replacing the CMOS battery, and testing the laptop with only one stick of RAM at the time in either slot with no luck. If I hold "D" while booting it does display the display diagnostic test so the LCD is fine.
At the moment it's still very random. Sometime it turns on fine, then right afterwards it would show no output, without touching the machine at all. If left untouched I don't hear any beeps, unlike the first time the problem appeared.
We appreciate you running the LCD BIST test to check the Display. As per the 6 beep code provided it indicates that the system has Video card failure. So, the Videocard needs to be replaced. Hence, private message us the service tag or the order number of the system to check the warranty status on it. If the system is under warranty, we can get the Video card replaced at Dell's cost. Click on my Username and select start conversation to send private message.