I sponsored for my brother and I received a letter of approval I-797. I want to know how much time can be taken by NVC for original visa. This letter is sent by Department of Homeland Security. Anybody can tell me about that case/\. Thanks a lot

You need to check the priority date with the current visa bulletin for FB-4 for his COB. This the VB for July 2010. Visa Bulletin for July 2010 (http://travel.state.gov/visa/bulletin/bulletin_5019.html)

For most countries, the FB-4 is processing for cases with a priority date of January 2001. You have a ways to wait.