Windows 7 BSOD & Crashes while playing games

BSOD & Crashes while playing games

Hi
I've been having random BSOD and crashes on my computer since I upgrade my computer from XP(32bit) to Windows7 (64bit). It happens every time I run programs that uses the graphics card at a significant amount (which is playing games =P). However, I didn't have any problems running those programs(games) before the upgrade. Aside from that, windows7 runs just smooth and stable.

Here is my computer specs:
- OS: Windows 7 x64
- Built in Feb 2010
- CPU: AMD AthlonII X4 620 2.6GHz Socket AM3 2MB L2 Cache
- Memory: OCZ3G1664GK OCZ DDR3 4GB(2X2048MB) D/C Kit PN
- Video Card: ATI Radeon HD 4650
- MotherBoard: ASUS M4A785TD-V EVO SKT.AM# AMD 785G/SB710 2XPCI-EX16 4D.DDR3-1600, 1XPCI-E 1X, GBLAN.SATA RAIN, DX10.1 ATX
- PowerSupply: ORZ600SXS2
- The most recent installation is done on last week.
I switched from XP 32bit to Wins7 x64 on Sept 2010.
And then I have re-installed Windows 7 for 3/4 times.

After reading on different tech forums, I believe that the problem is caused by my graphic driver base on the error information(atikmpag) when having BSOD. Therefore, I've done the following set up in Catalyst Control Center Cusing:
I go to Options/Profiles/Profiles Manager. Create a new profile. Under composition and checked "ATI Overdrive". Save and Close, but did not activate it at that moment.
Then I go to: C:\Users\{yourusername}\AppData\Local\ATI\ACE\Profiles
Open the xml document with the name of the profile I just created and change the values of the Clock and Memory speeds to look like this:
Feature name="CoreClockTarget_0"
Property name="Want_0" value="50000"
Property name="Want_1" value="60000"
Property name="Want_2" value="85000"
Feature
Feature name="MemoryClockTarget_0"
Property name="Want_0" value="90000"
Property name="Want_1" value="90000"
Property name="Want_2" value="120000"

Save and close. Finally, go back to CCC and activate this profile.
After doing that, I still have the same graphics problem. I really don't know what else can I do. All my drivers should be up to date. My best guess is that there might be some conflicts between the graphic drives and the hardwares of my computer.

A bunch of my minidumps is attached. Thanks so much for any help you could offer!! I really appreciate it.