problem playing games with new graphics card. plz help!!

I have recenlty replaced my old radeon 9200 graphics card with a Nvidia GeForce 6200. Since the swap i have been having problems with any game i play. The game wil load and begin playing smoothly, but then at random the game will crash, bringing up windows error reporter. I have unistalled the old drivers and unpdated the new ones. Anyone got any ideas?


This is my DxDiag Report
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System Information
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Operating System: Windows XP Home Edition (5.1, Build 2600) Service Pack 2 (2600.xpsp_sp2_gdr.070227-2254)
System Manufacturer: MEDIONPC
System Model: MS-7042
BIOS: Phoenix - AwardBIOS v6.00PG
Processor: Intel(R) Celeron(R) CPU 2.80GHz
Memory: 768MB RAM
Page File: 376MB used, 1500MB available
Windows Dir: C:\WINDOWS
DirectX Version: DirectX 9.0c (4.09.0000.0904)
DX Setup Parameters: Not found
DxDiag Version: 5.03.2600.2180 32bit Unicode

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DxDiag Notes
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DirectX Files Tab: No problems found.
Display Tab 1: No problems found.
Sound Tab 1: No problems found.
Sound Tab 2: No problems found.
Music Tab: No problems found.
Input Tab: No problems found.
Network Tab: No problems found.

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Display Devices
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Card name: NVIDIA GeForce 6200
Manufacturer: NVIDIA
Chip type: GeForce 6200
DAC type: Integrated RAMDAC
Device Key: Enum\PCI\VEN_10DE&DEV_0221&SUBSYS_00000000&REV_A1
Display Memory: 128.0 MB
Current Mode: 1024 x 768 (32 bit) (60Hz)
Monitor: Plug and Play Monitor
Monitor Max Res: 1600,1200
Driver Name: nv4_disp.dll
Driver Version: 6.14.0010.7801 (English)
DDI Version: 9 (or higher)
Driver Attributes: Final Retail
Driver Date/Size: 8/2/2005 16:35:00, 3908864 bytes
WHQL Logo'd: Yes
WHQL Date Stamp: n/a
VDD: n/a
Mini VDD: nv4_mini.sys etc..

Need anything else plz ask i will reply as promptly as possible. Thx