I've been scanning the posts over the last couple of days trying to find a solution to the crashing I have in the game and I've noticed something. If you go through the random crash threads, some times the blame falls with Nvidia for their graphic cards, and other times it seems to fall on ATI/AMD for their cards. Now, I'm not the brightest crayon in the box, but if both companies seem to be getting the blame for the crashes, doesn't it seem like maybe it's not the cards or drivers, but the programming of the game itself? I bought HOMM V and it crashed, I bought HOMM V: HOH and it crashed, now I Have HOMM V: TOTE and it crashes. All crash at about the same point. My system runs every other game just fine (Dual core 3.0, 2 gig ram, X1950 vid card), but this series locks up my system every time. I'm done. Ubi has gotten $130 from me for these three games, and until they care to answer some of the problems they seem to have created, I quit. They've killed off the Might and Magic franchise as far as I'm concerned. I have a 360 as well as my two pc's and I'm not buying anything else from this company. Ubi has put their money into their Tom Clancy series, let them have it. Sell M&M to someone who will at least act like they care. I've played M&M since it's inception, I won't be playing anymore.

uh I have run hommV on my computer that has been totally changed 3 times since it was released and each time I never had any problems that were related to the video cards!! Most of the time if you have a crash or lock-up; it is likely the video card is over-heating or the system has ran out of resources. Or you have your settings for the video card set wrong.
On my NVidia cards I always make sure I have the "let the program decide" or what-ever it says. And it works fine for me. So don't blame Nival or UBI for operator error!!

Same here mechnic, the only crashes I ever had were early game issues that one of the patches fixed.
Totally random crashes are usually down to the users computer, a faulty memory module is a likely suspect, or some background process starting, like a virus scan, or some program looking for updates.

In the op's first (of 2) posts he outlined his problem and posted a dxdiag which is better than most question askers around these parts (look at the first few threads in the h5 general discussion).

No one replied.

An x1950 should be more than adequate (since it runs fine on my x800). The directx9 appears to be up to date.

I would say go through the official help channel offered by UBI in the manual...but they are notoriously unhelpful. This is a fan forum so I wouldn't expect much help here though there are some who take pity on us less knowledgeable ones.