Need help in setting up Dual Monitors on XPS 8300

I have been using Dell XPS 8300 which is having AMD Radeon HD 1GB DDR3 Video card and it has a DVI, HDMI as well as VGA ports and now I am willing to setup dual monitors on the same, I am having two monitors that are having VGA connections and I have hooked up the VGA connections without any issues but then I am not able to get the second monitor work, by now I had tried out DVI-D to VGA connector but then I don’t know why the system was just not recognizing the second monitor, later I tried using DVI-D to HDMI to VGA connector and then the monitor was getting detected by the system but then the I was not able to get anything on the screen, I am quite sure that the second monitor works fine as I was using it with one of my older XPS, I have tried contacting the Dell support for the same and have addressed them everything along with the solutions that I had tried but then they were not able to help me out, they has suggested me to get an HDMI to VGA cable so when I checked out for the same in the local stores then they said that it wont work out for me, so is there anyone who can help me out with the same, I am not willing to replace the monitor as I am quite sure that it is working fine and it wont be of any use, I have bought the XPS 8300 as it supports dual monitors and VGA and DVI but then I am not able to get them work, is there anyone who can help me out fixing this??

In that case I just wanted to know that have you checked out the BIOS Setup by pressing F2 while the Windows starts loading, if not then open the BIOS Setup and then go through the graphics configuration setting and make sure that you are enabling “Intel Multiple Monitor Feature” after changing the same make sure that you are saving the changes before exiting BIOS and then rebooting the machine otherwise the changes wont take effect, when you are done with the same then just go through the below article for further help.
Guided Help: Dual monitor setup is easy in Windows 7!
Move windows between multiple monitors
Other than this also go through the Control Panel for your video card and then check out if there is a setting for enabling dual monitors as well, just check out these things and then let me know what you get, if you have any further queries then feel free to ask. Hope that helps.

Yes you can perform what has been mentioned in the above post but then before trying out the same just makes sure that you are not connecting the dual monitors but then you are connecting them to the correct outputs on the add-in video card, I also want you to post the exact model of the graphic card that you are having, I meant that you have just posted that you are having a ADM Radeon HD 1GB DDR3 Video card but then there should be a model number like 6450, 6750 etc so just6 check out for the same and mention it in the next post, have you checked out for any settings in the ATI Catalyst Control Center control panel for enabling the dual monitors, I am not very sure about the path but then I think there must be some setting out there for enabling the dual monitors, other than this I also want you to make sure whether the card is DVI-d or DVI-I and you are using the respected cable for the same, I just wanted to add here that for supporting a VGA monitor the port on the card as well as the cable/adaptor should have 24 pins (3 rows of 8) along with 5 pins on right, you can refer to the below image for the same.
http://i50.tinypic.com/24v4e9t.jpg
Ssince you have mentioned that the VGA>VGA is working for one monitor, so I wanted to know that when you are connecting just one monitor using DVi>VGA then is it working or not?? Just check out these things and post back the response you are getting for the test I have suggested.

I have tried changing the graphics config in the bios and I have gone through the links that you have posted above as well but then I am still left with the same,, I have connected the monitors to the correct outputs on the add-in video card, the video card is ADM Radeon HD 6450 I should have posted the same earlier, I have checked out the Catalyst Control Center and things are appearing to be fine there, the card is having DVI-d and it is not having extra 4 pins, where as the monitors is having only VGA ports as I have already mentioned above, I have tried out connecting DVI to VGA only using only one monitor but then it is not making any difference and I am not able to get it work, some people have suggested me to try out uninstalling and reinstalling the video card driver and updating it to the latest as well and I have tried out the same and even they did not helped. I have also tried using a monitor which is having a DVI port and cable but then it is not working after hooking up, it appears as if I am having a bad connector but then I am not sure about the same. Is there anything I can check out, I need to get them working somehow, so please help.

I will like to inform you that if the if the video card that you are having is just having 3x8 set of pins on the left side as I have posted the above image and not the 5 pins on the right then it is not capable of supporting VGA monitor and I don’t think that you will be able to get the second monitor working no matter what you try, the 5 pins are for carrying the VGA signal and if they are not there then you won’t be having any luck with the same, if you want to use two monitors then either you will have to get one new monitor with a DVI port or you will have to get a DVI-i video card having 5 extra pins so as to support the VGA monitor that you are having, it on you to decide the best choice, so just get any one of them and if you have any further issues with the same then post it here, we will try to help you out with it. Hope that helps.