We need dxdiag and files from this folder for solve your problem. C:\Users\<Name>\AppData\Local\Arma 3 Alpha\

Can you upload somewhere in winrar package please?
When package will be smaller than 5,000k, so you can attach here. Thank you.

http://feedback.arma3.com/how-to-user.html.html

Uploaded, thank you.

I don't see attached files, may be too big size of package and then files were not save.

Fixed. File was too large.

Can you try kill all unnecessary application before start Arma?

I've made a note in another similar issue before. The steam.exe gets stuck on some CreateInrerface method (can't recall the offset), it's reported to be in suspended state. If I attempt to inspect it's stack with Process Explorer the steam.exe suddenly dies and Arma gets launched. Here is the reported stack http://i.imgur.com/SGmbJlP.png

Thank you pystub, I kind of figured the dxdiag routine wasn't really gonna tell us anything.

Can you please clean crash dump folder and attach new rpt file when this issue will happen again? Every rtp file has time in name, so you can easily find correct one. Thank you.

Closing due to lack of information / no response in a long time.

If this issue is still reproducable for you, please create a new ticket and make sure to include all necessary info / files.