Loop No Boot Running Dual Graphics for 5-6 months - Hum?

Hi All,

I've been running a K7s5a pro with two Nvidia graphics cards. The system have been stable for 3-4 months, but within the last 1-2 months it developed issues with conflict during boot.

Win Xp reported it as a driver issue with Nvidia. System is updated with the latest unified driver from Nvidia and latest Win xp pro updates. The system is stable running dual monitors at 1024 x 768 at 70 hz. System will allow me to reboot hot from XP. The issue is during cold bootup the system just goes into a loop and continue to reboot.

My System:
Mobo: K7s5a pro, AMIBIOS VER 1.21.11, 2001, 2003s
CPU: AMD 2400+ (running temp typ load 100F-120F)
Graphic: AGP Nvidia Gforce 4 mx 400 w/64mb
PCI Nvidia Gforce 2 mx 200/400 w/32mb
Nvidia unified driver latest update
Memory: PC2100 (133x2=266), 512mb + 256mb (3,6,4) norm, norm
HD: Western Digital 80gb w/8mb
Power Supply: 450 Watts (12V, 5V, 3.3V and CPU voltage are all in spec. under load)
Others: dvd, cdrw, floppy, usb universal reader
Bios Setting:
Graphic Apperture: 128mb
ACPI: yes, Power Management: enable
Serial Ports: disable, Parallel Ports: disable, Game Port: disable, Midi Port: disable, OnBoard Pci IDE: Both, Sound: Enable, Modem: disable, Lan: enable, USB enable
Plug and Play: yes, AGP 4X, AGP primary graphic, Allocate IRQ to PCI bus: yes

The only hardware issue I can think of is the IRQ at 10 and 11. IRQ 10 has sound and USB. IRQ 11 have both graphics drivers and USB.

1) Are the IRQ sharing setting up a conflict that is preventing boot?
2) Is there an issue with Nvidia unified driver that is trying to control the dual graphics display and the Win xp pro which allows spanning onto dual monitors?
3) The system was stable for couple of days after Microsoft people help me repair the OS. ...but now it is unstable with dual graphics again.

I have removed the second graphics card. Reset the CMOS. Loaded a very conservative setting and turned everything off in the bios that is not used as before. The system have been booted with CD support. I found no conflicts at this time and no boot failures with single graphics card. Otherwise I find these motherboards very stable. I have one system running for my kids for 2 years without any issues. Never opened it after initial build.

The problem is onces I used dual graphics for 5-6 months; I find it very difficult to go back to one monitor. The productivity and ability to compare and open different items and work have suffered greatly. I want my dual graphic cards and monitors.

Are there anyone out there who has suffered the same issue with the latest updates running dual graphics cards, monitors on the ECS K7S5A Pro motherboard?