PC1: Windows 7 and Linux distros in 2 separate HDs. Leap 15 uses nvidia driver. Video card is GT520.

PC2: Windows 7 with GT730 video card.

I just installed the Linux disk that I removed from PC1 and put it in PC2. After booting, Leap 15 with KDE 64-bit shows very tiny user id and password boxes. After logging in, the screen shows only the top 50% of the task bar at the bottom of the screen. In other words, I only saw the top 50% of the icons on the task bar. Display is HDMI 1360 x 768.

By the way, Debian 9.5 KDE 64-bit in the same Linux disk shows no problems when moving over. It uses nouveau as default graphic driver.

Could you please show me how to fix this problem?

Thanks a lot for your help.