New cpu needed new bios, now I can't boot original cpu

MrJelliBelli

Honorable
Jul 3, 2013
15
0
10,510
I bought an amd fx 8350 cpu for my M5A78L-M LX V2 motherboard. I installed the cpu and when I turned on my pc nothing happened. No beep and no output to the screen. I searched around and it would seem I need an updated bios. I downloaded the appropriate bios and tried turning on the pc with the new cpu to no avail since it can't even get into the boot screen. Then I tried putting in the old cpu, a Phenom II X2 560, to install the bios, but now it's acting up. It beeps on startup and the screen registers an output but it's just black with an occasional jump to an unfamiliar boot screen, but that just flashes by in an instant.

How can I access my boot screen, have I wrecked my old cpu? Or is there some other solution?

(I've also tried removing the battery from the motherboard with both the old and new cpu.)