Understand.  to fully achieve your Dell 24” monitor 1080p resolution you can consider hdmi/DP to DVI adapter (all of which are digital).  with analog VGA there may be a problem reaching optimal resolution.
I ordered XPS 8940 on Amazon: [URL] , there is no back photo. I went to Dell Official website and check XPS 8940 back photo (attached), before placing the order. Here is Dell official page: [URL]  Now I have received my XPS 8940, which is different from the photo posted on Dell Official website. My PC has much fewer ports(see attached), how many monitors can my PC connect to? Why my XPS 8940 is different from the photo posted on Dell website. Thanks.   [IMAGE]My XPS 8940[IMAGE]From Dell Official Webpage
XPS 8940, Amazon different from Dell?