My dell OPTIPLEX 780 case won't open

[Jawaad]

The latch fly goes in and out but it doesn't open I got it refurbished

[DELL-Ravi Ch]

Hi Jawaad,

Please Pull back the cover release latch and tilt the system cover from the top outward to open the cover.

Also, do use the service manual under manuals tab in the link : http://dell.to/2g6FSw3

[speedstep]

If the cover is bent you may have to pry off.  USFF isnt the same as MT DT SFF

http://www.dell.com/support/home/us/en/04/product-support/product/optiplex-780/manuals

[Jawaad]

Can I install a Sapphire Radeon HD 6450 into a Dell OptiPlex 780 SFF?

[speedstep]

ASUS Silent EAH6450 fits in all models some of the sapphire units are too tall and too wide to fit.

Low profile fanless versions that do not use 2 slots are likely fine.

This Sapphire 6450 for example although Low profile DOES NOT  fit.