I'm having an ongoing problem with my Samsung 955df monitor. When the monitor has been off, in standby or on screen saver for awhile and I start it up the picture is great. Within minutes it slowly starts to degrade (goes out of focus)until it's barely readable. This monitor has 2 focus controls (edge and middle) and I've tried adjusting both after it is warmed up (1 hour or so), to no avail. I can get 1 area focused, at the expense of the others (left, middle or right). I've tried different refresh rates and resolutions with no results. I'm wondering if overheating may be causing this...the unit has never been opened and the environment here is pretty dusty (I regularly blow out my tower with dry aerosol). Or am I drawing at straws with that idea?

ASUS A7M266 MB,
AMD Athlon XP2100+ CPU,
PNY Verto GeForce4 ti4600 graphics,
1gb Crucial RAM

Thanks.

Not good news, I'm afraid. You have a bad flyback (a/k/a integrated high-voltage transformer -- it runs hot) or a problem with the dynamic-focus circuitry. The focus voltages are derived from a resistor network integrated into the IHVT, then modulated for edge focus. If one of the plated connections becomes thermally intermittent, the voltages (hence focus) will drift.

The IHVT is the second-most expensive component in a monitor.

The monitor might still be under warranty.