Is the X-ecuter2 bios 256k or 1024k?

[vmehta211]

I have a cheapmod chip installed on my xbox with the X-ecuter2 bios on it. When I use the backup feature of EvoX it backs up my bios as a 1024k file called bios.bin. However, I have recently downloaded the new version of the X-ecuter2 bios (4977) and it is only 256k. I was wondering if I got a bad copy of the bios or what is the reason for the discrepency between the two X-ecuter2 bioses?