Hey thanks for your help. Unfortunately it didn't help. The BSOD doesn't hit me, but the sims lock up when I try to run them.
FYI - here is the solution????? from Nvidia in anyone else is interested.
Frog
There are several factors that can contribute to system instability. Since the graphic card is always drawing to your screen, Windows will often report the graphics card or its drivers as the problematic device after a system error. In most cases, the problem is caused by another device or component in your system such as the motherboard, system memory, power supply or hard drive. Here are some tips to help you troubleshoot your computer.
Close unnecessary programs and processes in Windows XP and Vista.
Right-click a blank space on the Windows Taskbar and select Task Manager.
Click the Applications tab to view the list of active programs.
Click on any program listed in this window and click the End Task button.
Repeat until all programs have been closed.
The following steps are to close unnecessary processes in task manager:
Click the Processes tab to view the list of active processes.
Click the User Name column header to organize the processes by your login.
Click on any program listed next to your Windows login, other than EXPLORER.EXE and TASKMGR.EXE, then select the End Process button.
(Do not close processes running under SYSTEM, LOCAL SERVICE, or NETWORK SERVICE.)
Repeat the previous instructions until all programs/processes associated to your Windows Login are closed except for the following two:
TASKMGR.EXE
EXPLORER.EXE
DWM.EXE (Vista only)
If you have installed NVIDIA nTune please uninstall this utility for troubleshooting purposes through Windows Control Panel Add / Remove Programs.
Thereafter, close task manager and try to reproduce the problem.
If you do not know who makes your motherboard chipset, please consult with your PC manufacturer or your motherboard manufacturer for more information.
The following motherboard BIOS settings are suggested for better stability, but are not required settings:
Assign IRQ to VGA Enabled
VGA palette snooping Disabled
PCI Latency Timer 128
Video BIOS Shadowing Disabled
Video RAM Shadowing Disabled
USWC Options Disabled
PnP O/S Installed Enabled
Video BIOS Cacheable Disabled
Video RAM Cacheable Disabled
AGP Graphics Aperture 64MB (or half of your total system memory)
Incompatible system memory or bad system memory can also lead to system instability. Please verify that your system memory has been tested and is compatible with your motherboard make and model. There are 3rd party utilities which allow you to test the integrity of your system memory. One such program is Memtest86 which is available as a free download from the following URL:
www.memtest86.com
Just as important is your CPU. If it is malfunctioning, it will cause system instability. There are 3rd party utilities to test your CPU. One such utility is Prime95 which features a torture test which reports to you any errors generated by the CPU. This utility may be downloaded from:
http://www.mersenne.org/freesoft.htm
If your NVIDIA Forceware display drivers are outdated, you may need to download and install the latest display drivers. You will find the latest Forceware unified display drivers for desktop graphic cards from our Software Downloads page at the following URL:
http://www.nvidia.com/content/drivers/drivers.asp
From the Software Downloads page, choose "Graphics Driver" from the first box - Choose the correct "Geforce Series " if you have a Geforce, Riva TNT2 or Vanta based graphics card. Choose Quadro if you have a Quadro based graphics card -> on the third box, choose the operating system you are using and then click the Go button. This will take you to the driver downloads page for your graphics card.
If your video card features active cooling, check that the fan on the video card is spinning. If it is not spinning, in particular when you are running a 3d application, then it can cause the video card to overheat. Last but not least, verify that your system meets the full minimum system requirements provided by your video card manufacturer.
If these steps do not resolve the problem, please contact the manufacturer of your video card (please note that NVIDIA does not manufacture video cards but only designs video chips). If you received your video card as part of a computer purchase, please contact the manufacturer of your computer.
Please feel free to contact us, if you have any further questions.
Regards,
NVIDIA, Customer Care.
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