BSoD x124 only with this game
0×124 is, in just about every case, a hardware problem and the fact that it’s gotten worse over time supports that. It has nothing to do with the game and x6’s being compatible else there’d be a lot more posts on this.
Make sure all your drivers are updated, then either lower your overclock or increase the cpu/HT volts. If you’re not overclocking, increase those voltages anyway as it means your chip’s probably seen more than it’s share of thermal cycling.
OP, I recently upgraded my GPU to a newer AMD (I also run the Phenom 1100t) and right away ran into the same issue as you (BSOD with GW2 only). After all the troubleshooting, it came down to a BIOS update for me.
BTW, it wasn’t the processor and there is nothing wrong with the Phenom 1100t and this game. I get an average of 70-80 FPS in PvE and the game runs buttery smooth (mostly highest settings). You have to keep in mind that even though you and I have a Phenom, there are still so many variables between our systems to account for issues.
(edited by Rabbiddog.7690)
It’s also worth checking all the hardware that you didn’t replace part for part for stability – this means run memtest on the memory, and if that checks out run intel burntest on the processor and run a graphics benchmark of your choice on the graphics card.
The fact that other games don’t produce the same BSOD doesn’t mean your hardware is fine and dandy, because GW2 is a really intensive game and puts more pressure on the CPU and GPU combined than pretty much any other game out there. Because the BSOD is limited to GW2 the most likely cause is an instability in the system that only shows up under high loads.
Also as Rabbiddog pointed out make sure to install the latest BIOS for your motherboard – the initial BIOS versions can often be quite buggy and cause all sorts of strange problems, so it’s always a good idea to update the BIOS if you run into a problem like this.
Also when you get a BSOD Windows normally creates a minidump file which might contain more clues than the BSOD error code as to the cause of the BSOD. There are some free utilities on the web than can analyze the minidump file for you or at least display it in a readable format.