I bought a used Dell desktop.  How do I get administrator rights?

You'll have to get the administrator password from the original owner, or you have to reinstall Windows from media.

There are tools to crack the admin account, but I don't believe the forum rules allow discussing these.

How can I post new question in Dell community?

How does one ask a question on Dell's community area??  

I formatted my PC and now can't install supportassist, and need that, to install drivers!

has anyone helped you? figured it out?

http://support.microsoft.com/kb/q555375

...is a dead link

Hello I have a Dell Optiplex 3020 Tower. I am wondering if I could put a sata 3 500gb SSD in this rig.

Yes you can as for the capacity, you need bracket to fit in the 3.5" space, I have SFF model.

Hello I own a dell optiplex 3020 tower and am wondering if the gtx1050 would work if I turned secure boot off. Thanks for your help. 

Hi, you need to post new question.