This seems to happen in many different drivers but it happened more often in newer versions such as 530 vs 525.
Then nvidia-modeset goes to 100%
There are many reports of this appearing since driver 4.70 and I can confirm I've seen this in various machines.
https://forums.de........
Everything was working fine but I believe when Iturned off "EDGE" in Big Boss everythign went haywire, at first my WiFi dropped, then 3G didn't work and I couldn't even make phone calls.
If you're having this trouble with your jailbroken 3GS running 3.0 firmware, make sure you don't turn off EDGE, it seems to disrupt all service to your phone.........