Okay, using Windows 7 here, on an XPS 8700. After removing all the previous graphics driver pieces (gt 720), and inserting the GTX 660, and rebooting, I get a black screen. No video at all, even the earliest video going through boot is not there, just a black screen. Is there any standard way of troubleshooting this problem? I believe that the Dell XPS 8700 BIOS is at fault, but I'm wondering if there's anything that I can do to make this work? Just a note, secure boot is disabled.
 
Thanks.

The latest BIOS is installed on the XPS 8700, BIOS A08. Guess I need to contact tech support, then.
 
Thanks!

Yes on both. Power supply is fine, and I connected the 6-pin power connector to the GTX 660. Everything went together nicely, card fit well, and the card fan was working and all. And, as I mentioned, the computer booted up Windows 7 just fine.
 
Thanks.

aaronjtwille
Did you find a solution here? I am having the exact same issue. Dell XPS8700 (Win 8 though) with GTX660. Everything is installed and double checked. I get only a black screen when starting up. Nothing at all.
Switched back to the 720 and everything worked fine. Please help, I can't imagine the card came bunk out of the box.

Yes, I did find a solution...I returned the Dell XPS 8700 and got a Lenovo K450e with a GTX 760 installed and 4GB more memory than the Dell had as well. The Lenovo is a really nice piece of hardware, very similar to the Dell XPS 8700...The only drawback I've found so far is that Lenovo installs a ton of crapware on their systems. I ended up going out and buying new Windows 8.1 media, since in the process of removing McAfee and the rest of their crap, Windows installer got damaged, and I couldn't install Windows programs anymore, or fix it. McAfee was really something, took over the system and would not allow me to do anything, including adjusting the settings on McAfee. I got no idea why Lenovo would pick them for what they put on systems that they sell, must get the best deal from them.
 
Anyways, really like the system that I have now, the graphics are much more in tune with the system than the GT 720 was, it was so underpowered it was pitiful. So I never did get the GTX 660 or Radeon HD 5770 installed on either system. I have the feeling that either would install just fine on the Lenovo, since I got the GTX 760 installed when I did a clean install, no problem. They seem to have their arms around writing a decent BIOS. The clean install that I did even includes working with UEFI set in the BIOS, so it works well with "secure boot".
 
Wish I had better news on the Dell, but I gave up on it while I could still return it. Wouldn't have minded keeping the Dell, but Dell has gotten to be very slow about dealing with problems that are critical to their customers. Sad. They never should have released the system in the first place without having tested some common off-the-shelf graphics cards, instead of just the special cut-down OEM graphics cards that they did test.