PC giving issues, 3870x2 the cause?

Description of the issue:
Low performance in games, lower than it should be. For example CoD4 with AA on 2x is only running at 25 FPS or so. Anno 1701, a game from 2006, is stuttering. However I'm not sure if those issues are related to my graphics card. In Anno, the performance doesn't increase by disabling the 8x AA. The stuttering stays the same and seems to be causing a stutter at about a 2 second interval when moving the view over an area with alot of objects. Playing Anno, my CPU is beeing used for 60% all the time and my RAM is 75% full.

I am using:
Vista Ultimate x64 SP1
Asus' graphics card drivers

My setup (all at stock speeds):
Asus Maximus Formula, bios 0907
Asus 3870x2
E8400
2gb of Corsair Dominator memory

What oh what should I do to get my computer working as it should be?

Thanks in advance

I actually changed from an 8800gts (G80) to a 3870x2. I had to reformat because the computer was acting up, however, after the reformat i have not had one problem since, 3870x2 is a great card, not the fastest for most games but its a great card stability wise. I have almost the exact same setup as you except i have 4GB and a Quad. If you haven't reformatted yet and are coming from an NVIDIA card you may want to try that. From personal expirience that worked for me.

I'd go with 8.4. I had the hotfix installed but it was causing corruption in Crysis so I dumped it. The 8.3 hotfix showed up as 8.4 though....

Well, I was able to determine the cause of my stuttering issues by watching the hardware monitor from RivaTuner. You can install it and monitor without over clocking or messing with settings. When I would run in to stuttering issues, I would see the clock on the GPU drop down to the power saving settings, then go back up. So, if you can I would use that and run a game in windowed mode (unless you have a 2nd display, or Everest Ultimate and an lcd on your keyboard )and watch the clocks.

Have you done anything to the O.S.? Maybe disable UAC, or disable paging file?

After Installing Catalyst 8.4 my stuttering issues have not returned. I believe it was the cure.

I noticed it during CnC3 all the time. Seemed like it was happening every 5 min or more. I also noticed it in The Witcher, but it happened rarely in that game.

My system has been running ok since 8.4.

I'm having an almost identical problem with the same setup. However it's only happening for me in 1 game specifically: Everquest 2. Crysis, CoD4, TF2, Bioshock, etc. all run like a dream. In EQ2 I get lots of stuttering/choppiness. I brought up the ATI OverDrive utility and noticed that my GPU was running at 300mhz while in game. I cranked everything up to extreme quality and found a laggy area to run around in, and the clock would occasionally jump up to 825 where it's supposed to be, but almost immediately dropped back down to 300 followed by a subsequent hitch/hangup where it would drop down to 5fps or less. Every single hitch/stutter corresponds to the GPU dropping back down to 300.

Any ideas on how to fix this? The problem happens with the 8.4 drivers, so the update didn't help. SoE suggested 8.3 since it's their recommended driver version for the game, but of course I tried it and it still does the same thing.

Here's some of my specs:

Vista Ultimate 64
ASUS Maximus Formula
ASUS 3870x2 @ stock
e8400 @ stock
4gb Corsair XMS
WD Raptor HD

The actual 8.4 CCC & Drivers. I did a complete uninstall and driver clean, rebooted, and installed the whole 8.4 package. The problem persists. Ironically, I just did the same process but with the old 8.1 CCC & drivers that came on the disc with the card, and the problem is somewhat fixed (probably due to the fact that it doesn't have ATI OverDrive on it). However I don't consider this a fix since 8.1 gives me numerous issues with other games. And before you ask, yes I also tried installing the 8.4 driver without the CCC but for some reason it doesn't fix the problem. I'm not sure why unless OverDrive is installed with the base driver regardless.

I'm at a loss. Swapping drivers each time I want to play a different game isn't really an acceptable solution for me