DPC Latency & Sound Dropouts

Recently I upgraded my computer hardware to a new motherboard, graphics card and processor. I moved my old hard disks (from my old hardware) into this new computer, turned it on and it started right up, I just had to re-validate Windows 7, which went without a hitch.Yesterday, I bought a new headset and started using it with my PC (before I was using desktop speakers), however, when I turned on some music, I was hearing a lot of stuttering/static while it was playing. I had this problem before, but it usually only happened when there was a program running that was taxing the CPU, and that isn't an issue now.I read around for a while last night about the issue, and it turns out that it's something called "DPC Latency", so I downloaded all the tools and tried to troubleshoot it for a few hours before I went to bed with no luck.So far I've tried:

-disabling HPET in bios & switching it to 64 bit mode (it was on 32 previously)
-turning off Powermizer on the Nvidia card
-disabling all USB ports one by one
-disabling all audio and network drivers
-changing the power settings for the CPU and HDD (tried this http://www.sevenforums.com/tutoria [...] -dipm.html
-updated all my drivers except by BIOS so far (I haven't tried that because it seems kind of risky, but I suppose I would do it as a last resort)

Another issue I was having was with my processor making this high pitched whistling noise, but when I turn off "disable processor idle" in the Windows power management area, it stops making noise. The weird thing to me is, it changes my dpclat.exe from full red bars to this for about 1-3 minutes (but after a few minutes it just goes back to full red bars, 28000μs):Before I went to bed last night, I turned on a 2 hour audio track and set it to loop with LatencyMon running. You can see in the screenshot below that the main culprits are:

-ndis.sys
-ataport.sys
-usbport.sys
-dxgkrnl.sys
-HDAudBus.sys

I've looked around on how to fix these individually, but I can't come up with anything at all. If I purchase a PCI sound card, would it fix these issues? I would prefer to fix it without having to do that, but if that's the only way to fix it for sure I can do it.