lag and conflicts

[grimtofu]

so ive been suffering from lag thats 2-3 sec long for both video and audio and sometimes games. i think it may have something to do with an out of date bios, as well as irq issues. its not codecs, drivers or viruses, as this is a new computer, on for less than a week or two (edit: i have also updated codecs, drivers, etc. to the newest drivers). heres my irq thingy:

i tried to edit the irqs manually, but it wont let me. a site i went to says that windows uses acpi or something to that effect to manage irqs, so im stumped. it also said that its possible to edit it in the bios, but as i said, mine is out of date (edit #2: the bios wont let me manage irqs). here is system info if its needed:
system: XP home
chipset: 82865G/PE/P/GV/82848P (p4 2.8 with ht)
mobo: D865GWV Intel
mem: 1024 mb
video card: GeForce 7600 GS Nvidia
sound card: integrated

 

[Sora]

Possibly your CPU is throttling itself? P4's run quite hot

 

[grimtofu]

could be. =/ it seems to run world of warcraft fine, as well as overlord. (both take up around 1/3 of the ram) and ive never seen the cpu usage go above 40 or 50%
(edit: the physical heat coming out of the box it barely noticable. it feels cool, actually)