BSOD away

I know, a lot for my first post, but I need help.
I have recently built a new system, my 5th, and the first on e that i have had trouble with. And trouble it is. BSOD, hangs, etc. No two BSODs are alike. Close and similar, but not alike. 0x1, 0xA, 0x7, 0x8, 0x8E, 0x116, 0x1A, among them, with varying faults attached. The mini-dumps, some attached, have identified Vista driver errors, others are Nvidia driver errors, and unspecified hardware errors. I( would note that the errors only occur when the system is stressed slightly. Any 2d or 3d application trips it, including every game. Not some, every. However, day to day computing may not cause a problem, it has not crashed there yet. But once I try a game, then either a hang, crash, or BSOD. And not modern 3d games alone, but dx7, dx8 and games not requiring intense or any complicated graphics.

Hence my dilemma: everything is wrong.

What I have done:

1. Clean reinstall of windows vista, scrubbed of old drivers and replaced with the latest.
2. The latest bios, chipset drivers.
3. Memory tested.
4. disk drives checked.
5. BFG (Video card maker) insists it is driver issue and that I contact Nvidia, forgetting of course that nvidia says contact the manufacturer of the board.
6. PSU is well Rated for the board, and is a replacement of a DOA psu.
7. Temperature and cooling are adequate. Errors occur irrespective of temperature of chip or chipset.

Interestly sometimes the error report comes back with "this problem has been fixed in SP1". Which of course would be easy since I already have SP1 installed. It has said that for two different nonn-hardware problems, one Nvidia's error, one MS. Neither mattered to my machine.
What I would like to know is
1. Any suggestions as to what protocols I should use to find out where these things are coming from, and should I just send the video card back?
2. Any driver I am missing? Is Vista the problem and should I switch to XP?
3. Any good places for premature burial spots that might have pose chances for reincarnation?

ww

This might be one of 2 things - one is a compatibility issue (most common between the graphics card driver and the motherboard) or two, faulty RAM. I would try swapping the Nvidia card for an ATi card and making sure that the RAM is on the list of approved RAM for the motherboard.

Thanks.
However, I don't have access to an ATi board. I tried buying one for my kid's computer last week and the local computer electronic's megastore didn't carry but one or two. Nearly all they had were Nvidia. I am assured by the respective manufacturers that the boards are compatible, albeit mine might be the exception. RAM checks ok through testing, but is not on the list of approved memories, although other OCZ memory was. No memory at the store was on the list, so it was difficult to purchase appropriate memory so I got as close as I could get. (telling me I should have mail-ordered.) I will try other memory tomorrow and see what happens. That I have, even though it too does not comply with specs.