Persona 4 40 fps, hits 60 fps if you go to window then back fullscreen

[Kazaki]

I don't know where to post this, so I'll give it a shot here.

I'm using the latest revision (1614) on Windows 7 RC x64. Specs are a C2D E7800, 4GB RAM, and an ATI 4770. EE and VU Clamps are on normal, the only speedhacks on are the ones down the middle.

I am using the GSDX plugin, latest revision SSE4, DirectX10. I am also using the newly introduced MSAA at x4. I've used both SuperVU and MicroVU.

The issue is when playing fullscreen, I'll sometimes enter a new area to have my FPS drop down to somewhere in the 40's. I ALT+TAB it back to into a window and it instantly hits 60 fps no problem. The weird part is I then ALT-TAB it back to fullscreen, and it still runs at 60 fps. This happens on the map area and the bedroom area.

The game is running at 720p.

Any ideas?

[rama]

Do you have vsync enabled?

[Kazaki]

Really?

I do, I'll see if turning if off makes a difference

[Kazaki]

It seems the slowdowns have gone away. I'll let you know if anything changes.

But with vsync on, why would alternating between a window and fullscreen mode fix the problem?