Visual C program runs 4x slower in Win8 than Win7 RRS feed

  • Question

  • I have a PC emulator I wrote in Visual C, and I recently switched from Windows 7 32-bit to Windows 8 64-bit. This is the program in question:


    When you exit the program, it tells you the average number of instructions per second it was able to emulate. The problem is that under Windows 7, it would consistently perform between 35 and 50 million instructions per second depending on what I was emulating in it. Under Windows 8, it never goes beyond around 12 or 13 million! I've tried compiling at both a 32-bit and 64-bit executable, and get the same results.

    What could possibly be causing this ridiculous slowdown? I use VS 2010, but have tried VS 2012 to see if it helped. No change, performance remains the same. I don't understand. It couldn't be the fact that I use SDL, could it? All video rendering is handled in a separate thread from the CPU emulator, and I have an AMD FX-8150 eight-core processor overclocked to 4.4 GHz.

    This makes no sense to me!

    • Moved by Amanda Zhu Thursday, September 12, 2013 5:43 AM
    Tuesday, September 10, 2013 3:15 PM


All replies

  • Hello,

    Thank you for your post.

    I am afraid that the issue is out of support range of VS General Question forum which mainly discusses WPF & SL designer, Visual Studio Guidance Automation Toolkit, Developer Documentation and Help System and Visual Studio Editor.

    I am moving your question to the moderator forum ("Where is the forum for..?"). The owner of the forum will direct you to a right forum.

    Since the issue is related to Windows version, maybe you can try to consult on Windows 8 community: http://answers.microsoft.com/en-us/windows/forum/windows_8 for better response.

    Best regards,

    MSDN Community Support

    Please remember to "Mark as Answer" the responses that resolved your issue. It is a common way to recognize those who have helped you, and makes it easier for other visitors to find the resolution later.

    • Edited by Amanda Zhu Thursday, September 12, 2013 5:43 AM edit
    Thursday, September 12, 2013 5:42 AM
  • I'd ask them over here.





    Regards, Dave Patrick ....
    Microsoft Certified Professional
    Microsoft MVP [Windows]

    Disclaimer: This posting is provided "AS IS" with no warranties or guarantees , and confers no rights.

    • Proposed as answer by Just Karl Thursday, September 12, 2013 2:01 PM
    • Marked as answer by Just Karl Friday, September 20, 2013 12:49 AM
    Thursday, September 12, 2013 9:20 AM