As many may experence this Throttling on Graphics Card has not found a fix. I currently using Radeon 4650 AGP
I know about powerplay to seem like they have not improved powerplay causing alot of High End Graphics to slow down drastically( even while playing game in window/fullscreen).
Well my GPU ran at full speed the day i put it on my computer first time than the next day GPU Start Throttling my GPU Core Clock Speed. (Did not overclock anyway) (My old graphics card was FX 5600 AGP)
47 C ~ 58 C (It slows down at any temp)
Fan Speed Normal 27% ~ 34%
1024x768 on All games Army Rage (Uses Shader Model 3.0) / A.V.A (Uses Unreal Engine and I use Shader Model 3.0) / Runescape HD . Except for Hero of Newerth (NO lag) getting FPS 15- 24 (No matter what setting i put on)
No GPU Core Speed on first day but the day after it started.
Normal Idle Core Clock 165MHZ Core Clock
While Playing games (Window/Fullscreen) 300MHZ Core Clock (Original 600 MHZ Core Clock First Only)