1. DO YOU CURRENTLY HAVE 5040 WORKING? Yes
2. OS model & version: W7 x64 Pro retail
3. Matrox driver version: v64_gxm-veos_2_06_00_026_whql
4. Firmware version: vxp2k_THDE_v2.3.40.t6.56
5. Graphics driver make & version: Vista x64 182.50 WHQL
6. Monitor make & version: Dell 2209WA x3
7. CPU make/model: Intel i7 920
8. Motherboard chipset: EVGA x58 SLI LE
9. Graphx card make/model: Nvidia MSI 295 GTX
10. Did you have to put in a custom res via NVidia CPL? No
11. If you have 5040 working, what's your refresh freq? 59Hz
None of the newer Nvidia drivers works, with any combination of matrox software FOR ME. The 19x series has considerable issues in general IMO, 191 killed my 280 GTX and has a faulty fan/temp control, and 195 has GPU memory errors and causes BSODs.
In my previous rig, I had a 280 GTX, Intel Core 2 Duo E8500, ASUS Rampage Formula, 4GB RAM, and did manage to run 5040x1050 with some of the newer drivers (191 series), on W7 x64 Pro retail with latest and the previously released Matrox software.