It sounds like you may have a data speed mismatch between what the bootload is using and what the PC/IDE is using.
If you put the Uno optiboot booloader on the chip, and then select Uno as board type, that may fix things for you.
It sounds like you may have a data speed mismatch between what the bootload is using and what the PC/IDE is using.
If you put the Uno optiboot booloader on the chip, and then select Uno as board type, that may fix things for you.