Please help. I have buit my 3rd PC, & am running XP (SP1) on the system spec'd below, but it is very unstable, with the following symptoms.

ATI AIW9700 Pro - TV picture is crisp, but often locks after 10 mins or so, esp when running other (non-intensive)apps (ie- Int. Exporer 6, Wordpad, Outlook). The sound also gets out of sync with the picture, & occasionally a horrible noise best described as "metallic/ feedback/ distortion".
Graphics periodically "hangs" when playing certain 3D games.

Sound - often gets out of sync with the TV. Occasionally MP3 playback seems to slow down, (like someone pressing down on an LP)

Mouse - My Logitech MX700 "wanders" across the screen on its own accord.

I have all the latest drivers & updates.

Dont know if these probs are related or all seperate issues, or if it is an incompatability problem. & Im not sure what to do to rectify this. Figure its either one, or a combinnation of Mobo, BIOS, IRQ's (Graphics & Soundcard both on IRQ 19), memory, Soundcard or Graphics card problems

My system is of a reasonable spec (see below)so having a few app's running shouldnt be a problem.

M'board - Asus A7N8X Deluxe
Processor - AMD 3200XP (Barton core)
RAM - 1.25 GB (PC3200)
Graphics/ TV Card - ATI AIW 9700 Pro
Soundcard - Hercules Fortissimo III 7.1
OS - Win XP (sp1)
Direct X - 9.0b

I cant afford to just replace everything, & I would be bery grateful for any suggestions

I've had this previously where Graphics card and sound card are on the same IRQ. Your manual should detail which PCI slots share which IRQs with system devices and AGP. Try moving the Sound card to another PCI slot.