PC/monitor using displayport wake up with lower resolution (sometimes)

AndreSmo

First, Congratulations for your new XPS 8500. I see that you manually have to reconfigure the resolution back to normal once your computer is back from sleep. I do not think that it is a problem with the displayport connection. However, I want you to update your Graphic card drivers from the AMD website. Here is the link to Autodetect your AMD driver , just download it and run the installation.
http://support.amd.com/us/gpudownload/windows/Pages/auto_detect.aspx

Secondly, would ask you to check if the Monitor settings are set to defaults.
Please reply back if you have any further questions.

Thanks,
Nikhil

Thanks Nikhil

I tried to download the new drive that you recomended and I got into problems.. I was able to download the tool according to the aforementioned link. I got a new drive according to the recomendation and I installed it. I selected  express installation and I followed the "next" all the way (I did not receive any warnings during installation). At the end of the instalation,  I got the message that the monitor may flicker/blank out and  now I started having problems. The monitor became "black" and I could not get it back at all(scary!!!!). After 15 minutes, I powered the computer off and when the computer restarted  I got the monitor working in lower resolution. I updated the resolution manually and it became sharper/clearer then before (very nice). However, I noticed that  the fan in the computer kept running much higher then usual,..all the time (noisy). I checked into the device manager and I could see that there was a yellow triangle (warning sign) by the AMD driver. It said that windows could not recognize the source of the driver....it may not be installed correctly....etc.Anyway, I rolled back to the older driver and the fan is running normally and the warning sign has disapeared. What is the problem with the drivers that i downloaded( I have an AMD 7800 on windows 7 64 bits)? Did I do any mistakes...I think I followed all the instructions and I did not see any warnings that the driver was some beta version....!  Does the XPS require that I download a driver from an official dell page in order to be recognized?? It was not funny to be without a monitor.....!

By the way,when I was looking for the original driver,  I first checked in the dell cd (drivers and utilities) and I could not see the original drivers for AMD 7800! Are they in the dell cd? How are they called in the dell cd???

About the monitor settings? Where should I check the monitor settings for the U2412...? Is it using the monitor buttons in windows 7 monitor setting??

Sorry, for all the questions from a user that is not very familiar with the PC inwards....;)

I appreciate that  you have done the installation correctly as suggested, however it might have been not updated correctly and thats the reason why the Device Manager showed a yellow bang which meant the installation was not successfull. So, I want you to install the updated graphic card drivers again from the same website but this time lets uninstall the previous drivers of AMD manually. In order to uninstall the old drivers, first right click on the AMD driver from the device manager and click "Uninstall" and then try also removing the software for AMD called as Catalyst center from the Control Panel>Programs and Features>Uninstall a program. After successfully doing this, restart is required now and then after it turns on check if you got no traces of AMD drivers , either in Programs or in Device manager.
To ensure this you can also try downloading revo uninstaller software from www.revouninstaller.com (just a free 30 day trial pack) and then scan it and check if you have got any traces of the old drivers remaining and if found it will ask you to delete it. (If none found then its good). Restart the system again and now use the tool from the AMD website I have given you and download and run the application again and then restart the system. The process might look long but its easy.
Dell Drivers and Utilities CD should have the AMD Drivers , if you can click on my name and Direct Message me your system's Service tag so that look for it and reply back.(No harm in having the drivers updated from AMDwebsite though). Regarding the sound from the fan, I want you run the BIOS update on the system using the link http://tinyurl.com/7a9sj32 which would restart the computer and thats normal.
And for the Monitor U2412, I meant the physical buttons on the Monitor to double check if you have set them to any prefered resolution.
Please reply for any further questions.

Just a question about removing the AMD Driver manually: Can I still use the monitor after unistalling the old drivers manually and before I have installed the new ones? The monitor is connected to the AMD board and how can I use it without drivers??  Is there some default drivers that enable the AMD board  to control the monitor after the drivers are removed manually...or do I need to connect the monitor to the integrated intel graphics in order to install the new AMD drivers?Of course,  I will need a monitor to install the new drivers.

I have installed the new BIOS A06 and it went ok,. Thanks!

I cannot see any updates for the AMD Radeon HD 7800 drivers in the official XPS 8500 Dell page. When are the AMD drivers update linked to the Dell homepage???

Yes, you can still use the monitor without the newer drivers having installed as Windows has the generic drivers already as default. Not really necessary that you have to get the monitor connected to the on board port for using it, as it can be used after removing the old drivers.
You may have the drivers page updated for your 7870 Video card soon on support site. Meanwhile, you can still use the link to get the latest driverrs from the AMD website.
Sorry that I had to reply you late on this. Hope everything is working fine now. 
Thanks