Cannot enter BIOS settings

Hi Guys,

I've been trying to solve an issue I have with a laptop I just bought (warranty period over). This has been driving me nuts. I tried every solutions  I could find online to no avail. I saw that many people have a similar problem (but in most case they can't boot in the OS). I'm out of ideas here so if anyone knows anything about this issue, please enlighten me.

Here goes:

Laptop: Dell Latitude E6530 with nVidia card NVS5200M with Optimus + Intel HD 4000 graphics.

Service tag: 8HFKJX1. Latest BIOS A20 installed successfully. Fresh install of Window 7 SP1. BIOS set to legacy boot mode, Fastboot set to "thorough"

My problem is: I can no longer enter into BIOS settings. Weird thing is, the computer boots normally and everything else is working just fine. All the peripherals work as expected, both graphic cards perform normally, keyboard, everything, name it...

I was able to enter BIOS when I receive the laptop (F2 at boot). One of the first things I did upon receiving the machine was to upgrade the BIOS to A20 per Dell instructions (using a bootable USB key into DOS). After that I could still enter BIOS (F2 during boot). Next I performed a fresh install of Win 7 SP1. I could still enter BIOS at that point, then one day out of the blue, I could not enter BIOS (There is no BIOS password BTW). I have no clue what caused this or at which point exactly this occurred.

So here is the sequences that causes the problem:

1- I power up on the laptop

2- When I see the Dell logo, then I hit F2 to enter Bios

3- The logo then disappears, I briefly see an underscore flashing on the screen and then blank screen, except for a very faint back-lighting (noticeable when my room is dark). I can increase or decrease the intensity of the backlighting using the built-in FN + arrow up keyboard function)

4- the only way to get out of this is by pressing the power button, then the laptop reboots.

Next: I reboot, then hit F12 after the Dell logo to enter the "One time boot menu" where I can change the boot sequence. This works. I can run the ePSA pre-boot diagnostic which works (bright screen all normal) and reports all hardware OK (except for the battery which is is reaching "end of life" although I can still run for about 45min on it).

From this menu there is an option to enter BIOS setup but this gives me the same blank screen as described above.

Here are some of the things I tried to no avail (repeating the"reboot then F2" sequence between each one):

-Used an external keyboard;

-removed battery, AC adapter and C-MOS battery, wait overnight then plug-in C-MOS battery + batt & AC power and reboot (got some message that the internal time needed to be reset);

-replaced the C-MOS battery with a brand new one (3.3 V solid);

-tried external monitor (but this laptop model only outputs to ext monitor after boot process);

-tried every imaginable combinations of FN+E, Alt+8 or whatever combinations suggested on the web.

-downgraded the BIOS to an earlier version,

-re-flashed the A20 BIOS (success no error).

All along I never got any beep indicating an error and the LED's never blinked in the sequence to indicate error.

My next step would be to replace the MOBO, but I can't understand that this would be a hardware problem since the computer boots normally each and every time and everything is working fine....

What am I missing? I looks like there is no video signal to the screen after entering BIOS... I am pretty sure I do get into BIOS setup after hitting F2 but I have no video signal (except for that faint back light). Keyboard seems to be working coz I can increase/decrease the backlight from the keyboard + it works fine once I am in Windows. I tried finding a keyboard key/combination to exit BIOS setup, but it doesn't seem that there is such a feature on this laptop model.

That's it! I'm losing my mind over this and I reached the end of my wits. Anyone up for the challenge?

Any help /suggestions would be immensely appreciated.

Thanks for making it this far...

Cheerio!