Help with my Acer Veriton M265 BIOS upgrade

Hello everybody!

I'm having a big problem and i could really use some help from all the experts here. I recently bought a second-hand Acer Veriton M265 desktop computer so i could play some LAN games with my son. It came with windows 10 x64 pre-installed and everything was working fine. I decided to downgrade the OS to windows 7 and update the computer bios so i downloaded the latest one from acer's page using the SNID on the side of computer. I got to the bios update page ok and downloaded the most recent one and proceeded to update it on windows using the program inside the zip file. It updated ok but when the computer restarted, i got a BIOS checksum error and won't allow me to boot to windows (or any other drive so i could use the old bios again). Apparently everything is working fine and i can enter the bios and check the new version number, change settings etc, but when i restart i get the same error. I tried removing the battery and used a brand new one, but no luck. Can anybody here advise me on what i should do next? Thank you so much for any help on this!

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IronFly

have you loaded BIOS default?

if not

enter BIOS, press F9 and then F10 to save and exit

DoutorHouse

Thank you so much for the quick reply. I tried that several times and didn't work. I still get the same "CMOS checksum Bad" error. Also tried all three possible jumper configurations on the board and still nothing. Any other ideas?

IronFly

so, if you load default then save and exit, system will not boot but gives you checksum error again?

that's not good.

i read you already changed the CMOS battery, please double check the voltage, must be over 2.5V to be safe.

also do a CMOS reset, unplug AC power, take off the CMOS battery, press power button twice and wait around 10 minutes; then put everything back and check if it's able to boot.

DoutorHouse

Ok, after almost giving up i finally managed to solve this. The fact that i could still enter the bios gave me some hope so i searched for some info on the internet and someone wrote somewhere that, in a situation like this one, i should unplug all pci cards, disks, etc, just leave 1 memory and the dvd/cd drive and try to boot again from the dvd/cd drive using a boot cd, like hiren's boot cd or something like that. At first, i didn't think it would work because the computer always seemed to "jump" to the bios first, but on my second attempt, i tried to press the F12 key until i reached the boot device options. When i did that, the boot menu appeared but nothing happened again, just the same BIOS error, so i tried again. This time, i forgot to connect the ps/2 keyboard and the computer gave the same error but not the "press F1 to access bios" etc and booted right to windows 10 again. I immediately flashed the bios again with the backup file i had made, restarted the computer and everything was ok again. Now my big doubt is WHY this happened in the first place. I know it's my fault for forcing a BIOS update with a bios file which apparently wasn't meant for my computer but which was at the acer support site. If i use my system S/N PSM25C0P01*********** or SNID ********** i always end up on the support page for an Acer Veriton M265 model, which is mine apparently.

https://www.acer.com/ac/en/US/content/support-product/1106?b=1&pn=PS.V880C.004

From all the 6 different bios there, only the first one works (version R01.A3L which will install but delete my S/N and SNID info from my computer and leave it blank) (the original i have is R01-A0L) and all others will mess the bios if forced applied with the flash program. Maybe there's a more recent different working bios elsewhere? Maybe this model never got a real bios update and the ones there are all wrong? Is there some way i can know this for sure or a program to find and download automatically the correct one? Thanks again for all your help!

[edited for privacy-please do not post personal or unique information such as but not limited to full names, email addresses, phone numbers, full serial numbers, etc.]

IronFly

ok, now i understand why you had that checksum error, by the way the BIOS flasher didn't do the correct job, telling you that BIOS version, can't be used on your system.

you were lucky enough to have your system be able to boot to BIOS and then booting to a working windows enviroment, normally this "cross-flashing" kills the CMOS.

for future reference:

How can i understand which version i need to download?

Laptop versions:
1.xx can only be updated using 1.xx versions
2.xx can only be updated using 2.xx versions (normally 2.xx version are labeled "not for upgrades")

Desktop versions:
R01.xx can only be updated using R01.xx versions
R11.xx can only be updated using R11.xx versions (normally R11.xx version are labeled "*not for upgrades")

"L" BIOS versions are Linux OS dedicated (example R01.xxL)

* what does it mean "not for upgrades"?
During the windows 7 to 8 transition, some PC models had different BIOS versions from factory, related to the installed OS.
Windows 8 PC got an UEFI BIOS
Windows 7 PC got a "Legacy" BIOS

So PC with Windows 7 installed from factory can't use the "not for upgrades" BIOS version, even if they were upgraded to Windows 8 or 10, since the factory BIOS was a different version compared to PC with Windows 8 from factory.

DoutorHouse

Thank you so much for the info! Since i got this pc second-hand, i didn't have much info about it and the restore partition was no longer there, apparently. Only thing i have is the System S/N and SNID and the bios info. Mine is a R01-A0L. So i probably should have only update to that R01-A3L one. Thanks again!