Touhou 6 random lag spikes

Every 10 seconds or so, the game freezes for about 0.2-0.5 seconds while reporting to run on constant 62.50 FPS. I'm running Win10, here's what I've tried:

• "OBS-fix", setting the graphics processor in the control panel to either integrated or GPU
• Setting the graphics processor in the Nvidia control panel
• Running in compatibility mode
• Adjusting high DPI settings
• Adding the DX8/DX9 compatibility dll to the game folder

Task manager reports a spike in CPU usage when the freeze happens (around +10% usage). Also unlike Th7 (which is running fine for me), Th6 doesn't use the graphics card (GPU1) and uses integrated graphics (GPU0) instead; only sometimes the GPU1 usage spikes to 15%. These spikes are sometimes at the same time as the lag, sometimes not.

Note that Th6 is the only game to have this issue and that the same game files worked on my old laptop that also ran Win10 just fine.

Is there any fix or option that I'm not aware of that can help? Thanks in advance!

Solution 1:

Have you tried the following things?

• Forcing the game program to use only a single CPU core via Task Manager or Process Explorer
• Disabling (via Configuration screen > Device Manager) one of the two graphics cards.
• Running an MD5/sha1 check of the files, especially the executable. To get a file-hash in powerShell, execute:

    Get-FileHash /path/to/th6/th6e.exe -Algorithm SHA256 | Format-List  

This will print three lines. Does the line printed under 'Hash' return the exact same string on both computers? Then the file is the same. Check that you copied the key game files correctly (the executable and any packed data files are good places to start. Don't check anything containing saved data as it will obviously differ if you've played at all on the new laptop).