Why does my Samsung GT-i9000 not detect USB connectivity (not a driver problem)? I have made several searches across many boards but failed at finding a solution for my problem yet, even though it's been reported by some.

My phone was working fine for about a month, I was using the mass-storage technique without a problem until it stopped working one day. 

Now, when I plug in my phone by usb to any computer, the connection screen will not come up, the battery charging icon sometimes fails to appear as well and I can hear the computer detecting a new device but it will not recognize it.

I did a hard reset on the phone, which ended up in 2.1 instead of the 2.2 i had, and the problem persists. 

I have tried everything, from usb debugging mode to uninstalling/reinstalling drivers, even tried with my friend's cable and it does the same thing...I am very frustrated!

Anybody got a fix for me?
How do you know it is not a driver problem?

You've tried different cables? hopefully one that is confirmed to work with another phone.

Have you tried a different computer?

If its still dead to USB- then it sounds like a hardware issue with the phone, if you're under warranty then take it back!