Acer Aspire 7745G dead ATI HD 5850M, probably even worse issues

Hello to everyone! This is my first post here but I'm a long time reader. I have an Aspire 7745G which history I don't know at all: it comes from a lot and the only thing I know for sure is that it has a damaged lcd but unfortunately there is a lot more than that...
First of all the one and only way to make the laptop boot properly is doing the cmos reset procedure EVERYTIME, even after a simple reboot. To reset this laptop it's necessary to remove the RTC battery and short two pads on the motherboard (almost impossible to do when using the laptop) so I've put two wires on the RTC battery socket and now I can do the reset procedure more comfortably from the outside. This way I can 'use' the laptop and everything works fine. No overheating, no lock-ups, everything seems fine apart from the fact that the HD 5850M has completely disappeared from the system. It isn't recognized even as a generic VGA card, the only video card found by device manager, cpu-z, gpu-z and everything else I've tried is the Intel HD Graphics, only one video card and not two like it should be.
I've thought of a corrupt ATI bios so I've extracted the ATI bios from the latest bios for the laptop (what's strange is that the bios size is only 60Kb, not 128Kb like the others I've seen and RBE says that it hasn't overdrive settings while all the rest is perfectly fine) and I've made a check both with atiflash and ati win flash to no avail: no ATI cards found (no matter how many switches I try, I've tried everything that makes sense).
I'm not new about ATI firmware flashing and recovery but this is the first time I'm facing it on a laptop and I fear that the approach could be slightly different because of the presence of switchable graphics but I couldn't find any clear advice about that, I don't know.
I'm confident that the problems (the need to reset the bios at each reboot or power on and the disappearing of the ATI card) could be related; it could be a faulty motherboard too but it is at least strange that a laptop with a bad motherboard has a so selective fault while it is working fine for what concerns all the rest (though not impossible for sure).
My question is "is there something to do or not?". I'm running out of ideas and I hope that someone around there could give me an hint. Thanks in advance!

 

Unfortunately anyone hasn't given me any advice so this thread is more or less useless. Could I at least ask if someone around here happens to have an Aspire 7745G like mine and could send to me a backup copy of its bios? I hope that someone could help me at least this way. Thanks anyway and have a good day!

 

I have same unit, how can I send you that bios?

 

Hey, I today have encountered the exact same problem, my ATI gpu is gone after a system crash, and my computer won't startup unless I reset the BIOS battery everytime.