If you're noticing slight white vertical lines in colored rectangles on your desktop icons and in the browser with your RX 6650 XT graphics card, it could potentially be a defect. However, before concluding it is a defect, you should try updating drivers, checking cables and connections, testing on different displays, adjusting monitor settings, and testing with different applications. If the issue persists, contact the manufacturer or retailer for further assistance and to determine if the graphics card needs to be replaced or repaired.
PC Hardware Specialist