installed the 5850 in another computer, which had a 5870 in it, and was functioning perfectly. so now this pc had 2 separate video systems so i could try and flash the bios in the 5850.
observations when this pc was powered on:
the cpu fan went to maximum rpm.
now there was no video signal coming out of the good card, the 5870,(back to black screen)
when the pci-e power connectors were removed from the 5850, but the card still in the pci-e slot, the video signal coming out of the 5870(good card) returned to normal. also, the fan on the 5850 was still running from power from the slot.
also noticed that when i disconnected just one power connector from the 5850, the video signal coming out of the 5870 was normal, but not when both connectors were disconnected.
the computer was not seeing the 5850, as it was not showing up in device manager, so, no opportunity to flash the bios.
looks like this 5850 is toast unless someone else has other ideas to try.