Vostro 3750 Screen Removed - Getting 8 Beeps

I've done this before with other (not Dell) laptops but I'm having a problem here. I've removed the LCD screen altogether so I'm left with the main body of the laptop and I want to use a regular VGA monitor with it. When I do that and power it up I get the 8 beeps warning that the LCD has failed and it will go no further. Is there any way I can stop this warning and have it boot properly and recognise the monitor? If I press F2 on start up (and then do Fn + F1) I can access the BIOS but I can't see anything in there that allows me to bypass it. Thanks.