alot of people are saying dells power supply cant handle 7870

Hi adam8278,

I am sorry to hear that the screen flashes black 2 to 3 times a day on your XPS 8500 computer. I suggest you to update the graphics card drivers to the latest version.  You can download the latest drivers for the AMD Radeon HD 7870 from the AMD web site provided below:
http://bit.ly/4lMPnn

Please let me know the status of the issue after updating the drivers.

all drivers are updated bios is updated and it still happens

Hi adam8278,

may I suggest upgrading the PSU to a good 550-600 W range.

If in doubt go slightly higher, as to give room for future upgrading.

And may I suggest going for the modular type, a godsend in these days of upgrades and fast technology.

all the best.

adam8278,

"alot of people are saying dells power supply cant handle 7870"

* They are wrong. All of the XPS 8500 Dell OEM (original equipment manufacturer) video cards are validated on our 460w power supply. Our 7870 at maximum will only use 190w. Perhaps they are mistakenly referring to the power supply requiremenst for the retail 7870? Download and run GPUZ. Compare the results to these -
Engine Clock = 1000MHz
Memory Clock = 1200MHZ
Operating Temperature = 50°F/10°C to 131°F/55°C

ok that still doesnt help original problem of screen going blank. it flashes to black then back to normal a few times a day

What version of Window? What version of BIOS?

Did you reseat the video card as Dell recommended? Not sure this applies to your specific card, but some video cards in the XPS 8500 need a support bracket inside the case. See if yours has a bracket or not. Chris M can probably tell you if this card is supposed to have the bracket.  Reseat the RAM modules too.

Look in Windows Event Viewer for errors at the time of a black-out. That might point you in the right direction.

Does this happen if you boot in Safe Mode?

Have you scanned thoroughly for malware recently?

You might also try updating the video driver to the latest available for this specific card and version of Windows.

yes everything is updated even bios. the pc isnt shutting down there are no errors in log the screen just goes black for a moment while its black i can still hear sound and the screen comes right back

I have solved problems with similar symptoms by changing the configuration of the NVIDIA graphics driver, so that it always operate in maximum performance mode (not in adaptable mode, which varies the performance state according to the load, to save energy). You could go to the graphics driver software and look for these configuration options. I cannot give specific instructions because I am not currently using AMD cards.

Could just be a bad video card. Get Dell to send you out a replacement so you can test it. You have the choice of asking for "Parts Only service" or "Onsite service". If the replacement video card has the same issue, that rules out the video cards as the culprit.