Trouble updating BIOS on Acer Aspire M3970

So I bought an Acer Aspire M3970 Desktop with windows 7 about 5 years ago, and recently I've decided I wanted to upgrade the CPU. It came with an Intel Core i5-2320 processor, and I want to upgrade to a Intel Core i7-3770 Processor. When I put the new CPU in and attempted to start up my PC, I got 4 beeps and the computer wouldn't turn on. I did some research and decided to try updating my BIOS and hope that would fix my problem. My current BIOS version is: American Megatrends Inc. P02-A0, and I'm pretty sure the one I want to be upgrading to is the P03-A3 (Found here: https://www.acer.com/ac/en/US/content/support-product/3673?b=1)

the readme file in the P03-A3 folder tells me I'm supposed to run the .bat file included in the folder, but I get this error: Given ROM file does not match existing BIOS size

Now I did some more research and I actually found someone who had a very similar problem to me: http://www.tomshardware.com/forum/328340-30-need-flashing-bios but the answers in that thread haven't really helped me figure out my problem. I also run into an issue where if I try to type any comands into the .exe file, it just tells me "hit any key to continue" and eventually closes.

Any suggestions? Thanks!