Sometimes you get an image, but red looks blue, or the contrast is horrific. This is usually a "JEIDA" vs. "VESA" data mapping issue, which is corrected by specific firmware variations.
Use a 4GB or 8GB drive formatted to FAT32 . Larger or high-speed USB 3.0 drives often fail to be recognized by the board. T.vst29.03 Firmware Upgrade