In order to reproduce this bug, please, download and install a 30-day free trial version of Vegas Pro at http://www.vegascreativesoftware.com/int/vegas-pro-edit and do tests with the files I provided. There are projects to run on machines with AMD A10-7800 and Intel processors
AMD APU A10-7800 is UNABLE to do a simple zoom in a JPEG image in Vegas Pro without problems! This bug occurs with almost JPEG images bigger than 1920x1080 pixels. So I need to convert these large JPEGs in TIFF files. But that's not the right thing to do, because TIFF files occupy too much space on the hard drive. TIFF files are huge files!
The problem is NOT with Vegas Pro! This works very well in computers with intel processor. So, the BUG occur only with AMD APU A10-7800 processors.