Video and Audio stuttering in XP

[CaptNKILL]

Hello, im working on a computer for someone at school and this problem is driving me nuts. The computer is used for a movie editing class and was built last year by students (but never had this problem until a few months ago).

Problems:

• Videos stutter and skip often in Adobe Premiere and Windows Media Player
• Some audio files skip in Windows Media Player and when Windows plays them
• Access to some files and programs seems slow

Solutions we tried:

• New display drivers (ATI catalyst 4.1)
• Disabled the audio in the BIOS
• Defragmented / Ran scandisk
• Ran Windows update (Downloaded DirectX 9.0b and Media Player 9)
• Lowered Hardware Acceleration levels in Windows and Media player
• Changed AGP Transfer Rate (PCI mode,1x,2x,4x)
• Enabled\Disabled AGP Fast Writes
• Changed swap file settings
• Changed startup options (so fewer programs start with windows)

System Specs:

• AK39N v1.1 Motherboard (KT400, onboard sound, onboard LAN)
• Athlon XP 2100+ CPU
• 512Mb PC-2100 DDR SDRAM
• 2x Seagate Barracuda ATA IV 80Gb Hard Drives
• ATI Radeon 8500 All In Wonder DV
• Sparkle 300W PSU
• US Robotics 56K Fax Modem
• Lite-On 52x CD-ROM
• Lite-On 52x24x52 CD-RW
• Sony 3.5 Floppy
• Windows XP Home Edition (all updated)

Any ideas are welcome.
Thanks guys.

[Redshift]

You could try a lower screen resolution if you haven't already also do a full virus and spyware / Malware scan there may be something eating up your resources.

Also when the problem is happening have a look in system monitor at your Ram and CPU utilisation it will help diagnose where the problem is.

[CaptNKILL]

I looked at the utilisation and it indicates that the atlon xp 2100+ is at 100% or else very high around 80-100.

[caperjack]

run the 2 spyware programs in my signature ,spybot and ad-aware ,install and then update them ,and scan and remove what they find