Here there are SONY VGN SZ640 Graphic Drivers for Windows 7 64 bit . Please follow the steps to download and update your computer.
If you can not find a driver for your Windows 7 64 bit system you can ask for the drivers at support#hpdriversupdateutility.com (Note: change # to @).

Step 1: -> Click the button to download SONY VGN SZ640 Graphic Driver and then run the installer on your Windows 7 64 bit.

Step 2: -> Click the "Start Scan" button to find out latest Graphic drivers for your Windows 7 64 bit

Step 3: -> After the step above, the out-dated Graphic drivers and other drivers will be found and new drivers will be available for download. Click the "Download" and "Install" to update your VGN SZ640 Graphic drivers by the software, shown below.

• GUID: {5E0F8816-36FB-4D25-A0FA-529CC7EFB8A5}
• Vendor: SONY
• Device: VGN SZ640 Graphic
• Windows Version: Windows 7 64 bit
• Download Size: 626301 bytes.
• Totoal Downloads: 14167 till 2015-05-9
• Version: 16.63.56.527
• Release: 2015-02-10
• Description: SONY VGN SZ640 Graphic driver for Windows 7 64 bit
• MD5 Enc: 2a38a4a9316c49e5a833517c45d31070
• 
  
• GUID: {F8233615-7B73-4D37-98B1-8A6CA68B9970}
• Vendor: SONY
• Device: VGN SZ640 Graphic
• Windows Version: Windows 7 64 bit
• Download Size: 573840 bytes.
• Totoal Downloads: 50099 till 2015-05-9
• Version: 4.35.53.410
• Release: 2015-04-28
• Description: SONY VGN SZ640 Graphic driver for Windows 7 64 bit
• MD5 Enc: 6512bd43d9caa6e02c990b0a82652dca