New build Asus P8H67-V mobo, i5-2500K cpu, running Win7.
Using mobo's HDMI port. PC's monitor is connected using a DVI cable.
Using a hardwired USB mouse. My Win7 taskbar is moved to the right side.
Connected HDMI cable from mobo to a Samsung LN46D550 TV set for the first time. When I boot, the post displays on both the monitor and the TV fine. Starting windows displays fine all the way up to when the desktop is displayed.
The desktop display "on the PC monitor" has a garbled Win7 background in the top 1/3 of the screen with normal looking desktop icons and taskbar in the lower 2/3rds of the screen. The mouse pointer is not visible but when I move the mouse around, the icons on the taskbar (at the right) highlight individually depending on the mouse position. IOW, normal mouse action but without the mouse cursor.
At the same time, the "TV set" displays a normal looking desktop background without any garbling but without any desktop icons, taskbar or mouse cursor displayed.
Then I powered the TV set off and did a power on boot of the PC. Same exact symptoms on the PC screen and mouse cursor is not visible. This seems to confirm that the TV setting is not the cause. --- Then, without restarting the PC with the bad display still on the PC monitor, I disconnected the HDMI cable from the TV set. The PC's screen reset to a completely normal desktop display but the mouse cursor was still not visible.