BSOD "Driver IRQL not less than or equal"

ok Specs,

Proc: Amd Athalan 1.26G
MoBo: Epox Ep - 8KHA+
Ram: DDR 333 512 One Stick
GPU (Graphics Processing Unit?): Sapphire Radeon 9600xt 256megs
PSU:Enhance Electrics ENP-0735, 350 Watt
OS: Windows XP pro

It crashes whenever I enter a large city in World of Warcraft, or if I try to load a character that is in a large city, no other time. It is not over heating and is far from random. I have re-installed WoW a couple times, replaced my video card(brand new now), sound card, and RAM. I caught a look at the blue screen, "Driver IRQL not less than or equal" was all I could get, which is what led me here. I shut off my auto restart and when the blue screen comes, it is just that, a blank blue screen. I have followed all the directions for a disk check and creating a new page file. I am out of options and so here is the minidumps since I re-installed Windows (no, it did not help). Thank you for any help you are willing to give,
Ken
Edit: I am having a number of memory conflicts, all but one pertain to the video card. I do not know how to remedy that or if it is a major problem.

Minidumps 3-4

Here are the third and fourth Minidumps.

It's very likely an IRQ or driver problem. Try uninstalling and reinstalling the latest drivers for your video card.

You can't change IRQs short of changing your HAL layer, but that's quite a bit of hassle and risk without looking into this further.

You may also want to verify your memory is not having issues, as it can create the same problem. Run this program overnight - www.memtest.org