Hello, I am trying to play high definition (1920*1080 @60i, M2TS with AVC and AC3) videos shot with my camcorder. A lot of anecdotes I found on the net say my system is fast enough for it, but I still see stuttering. The one main problem I am trying to solve, is that the CoreAVC codec is not detecting DXVA and therefore the CPU has to do all the work. Hardware: Core Duo T2500 (2 cores @ 2.0 GHz) 1 GB DRAM ATI Mobility Radeon X1600, 256 MB Software: Windows XP SP2 DirectX 9.0c CoreAVC (set to use DXVA, HW deinterlacing, skip deblocking, high preference) Media player classic home cinema 1.5, all internal filters disabled Also tried with Windows Media Player 9 AC3Filter used to decode the audio This is a "clean system" without many apps installed, it was setup from scratch for media playback. No anti-viruses, malware, etc. slowing things down. I have tried two versions of the ATI (AMD) Radeon X1600 driver: 8.390 (circa Catalyst 8.9 time frame) 8.593 (from Catalyst 10.2 legacy driver set, after applying Mobility Modder) No matter what I do, CoreAVC won't operate in DXVA mode (tray icon remains blue, never turns red). According to MPC-HC, the stack of filters being used looks very simple and correct: Haali media splitter CoreAVC Video renderer AC3Filter Default directsound device ...so there are no extraneous filters slowing things down. I read lots of old postings (from 2007 and before) reporting success with CoreAVC and DXVA, but also heard mention of ATI somehow messing up DXVA support starting with the Catalyst 9.1 driver. I really want to know, from anybody who got DXVA working on an X1600, what version of the ATI/AMD driver you were using. Is there any utility to test whether the DXVA API is working/accessible on my system? Lastly, please do not say "Buy a new computer". There are many off-topic reasons why I need to keep this system.