I have purchased both a 950 ftw and a 750 ti ftw from evga. The 750 was doing great but I had enough for a 950 after a year and my brother needed a graphics card. So I bought the 950 and it was working fine at first but my brother took it out to test something. When I got it back from him my computer would not post. But the 750 worked fine. I got the 950 tested in the shop and it worked fine. But it still wont work in my pc but the 750 does. all drivers are up to date btw. And the mobo makes 2 short beeps with the 950 in but not with 750.
Any help would be appreciated

 

Oh and I forgot to mention my pc is a Dell XPS 720 H2C
 

Try reflashing the latest motherboard bios to see if it helps fix the issue.

Thank you for you post. But I heard reflashing is very risky and I have never done that before.
I am running the A05 bios.
Thank you

thing is you said it was working fine on the bios you all ready had ,so ? 
 
''So I bought the 950 and it was working fine at first but my brother took it out to test something.'''
 
don't show 2 beeps  as a code ??
 
https://www.manualslib.com/manual/553498/Dell-Xps-720-H2c.html?page=114#manual
 
I'd find out exactly  what your brother did  -  may try to clear cmos   then try to bot with the 900 card   in it after this -    if all else fails then try what sajin said  ?   thing is you know for sure it was working fully on your bios you have all ready  ???
 
you know when it comes to buddies and family  ''no good deed goes unpunished '' 

Thank you, I watched him install it and it was a normal install. I cleared the Cmos, I will try that again.
When I first got it and installed it the 950 worked fine for a few weeks until it was uninstalled.
I am very sorry for bothering you folks. Should I go to toms hardware because it seems like the graphics card is fine.
Thanks again. 

cant say ?  I pull cards a lot for things like cleaning and maybe a card swap  to check something [NVidia to amd  back to NVidia what ever and  so on ]  but   ??....   thing is  I would uninstall the driver  using the working card   and get things back down to windows default standard  vga driver   [fail safe driver built in to windows OS]    then remove the working card  - clear cmos   -   put the 950 back in and boot   -
 
now at that point you should get at least display for like entering the bios  screen  [ matter of fact should all ways get that anyway ]  if not ??    to me if it worked once should work 100 times just the same if nothing changed out side of the card  ..
 
I guess you rechecked the card was properly seated in the slot and any psu power leads were properly plugged in  and seated firmly to insure they all got good contact/ connections ??
 
to be honest being a dell  and how they are  I am surprised  the 900 card worked at all with out the latest bios and if the bios is updated enough to support any newer cards over a 600 series anyway 
 
like there xps 8700  would not support any newer cards w until dell released the A-10 bios  that gave it support for the 900 series   
 
I like this part  maybe like your experiencing ??
 
''   Just to emphasize if it's isn't clear -- the 970 does work perfectly that first time that it does boot.  No crashes, great 3D performance.  You just can't boot again without physically taking it out, booting, putting it back in.''
http://en.community.dell.com/support-forums/desktop/f/3515/t/19601491
 
so your dealing with dell   and looks like you may need them to give you a good new bios for newer cards  ?

Thanks I will try that. 

I have an XPS 720 h2c. Will the xps 8700 a10 bios update work with it? Thanks again.
 
 

I would not try it   a motherboards bios is just for that  board   never cross bios  between different boards / models  .     contact dell support   with the issue and get there input   maybe just on of them series of computers that cant support anything over a gtx 600 series  or a low 700 series like a 750ti  at best ??   with the 900 series things got ''funny''  and not so plug and play anymore  .
 
I would try dell or use there forums   for input on this from dell guys  that may have better insight   on what works and what don't   its a dell proprietary motherboard with a dell proprietary bios
 
looks like a 750ti will work ?
 
  http://en.community.dell.com/support-forums/desktop/f/3515/p/19596628/20791431#20791431