That's a problem related to the hardware acceleration of your video card in dual-monitor mode. Also, try setting the output of DOSBox to overlay.

I solve it
in the screen properties it marks the second monitor as primary. it even maintained the configuration of the whole appearance.
now it works well in the second, and to full screen in the second.
but in the first one that gives the same problems.
as me I need that that works in the second, my problem this resolved one

anyway, if you can solve totally. thank you

i try overlay, primary monitor ok (blurry some programs), black windows when move to second monitor. when move windows to primary, windows view correct

Hi,

got a similar problem. When running DosBox windowed (on primary monitor, don't have a second one) CPU usage constantly is at 100%, no matter how low I set cycles, and the rest of the system gets completely unresponsive.

My config:
Athlon 64 FX 55
ATI Radeon X800 XT
2GB RAM
Win XP SP 2
ATI Catalyst 4.12
DosBox 0.63

I have already found a few other posts on this forum that address this problem, but found no real solution for me yet...

What I have found out for myself:
- when I set the Desktop to 16 bit depth (default is 32 bit), CPU usage in windowed mode is going down, but not as much as I would like and expect.
- when I disable hardware acceleration in the Windows display control panel (move slider to the third position from the left, thus disabling DirectDraw acceleration), CPU usage in windowed mode is ok!
- CPU usage in FULLSCREEN mode is ok, but only in "surface" rendering. Overlay, DirectDraw and OpenGL rendering increase CPU usage again, allthough not up to 100%.

So I would think that this might be a video card / ATI driver issue?
I would like to add that I do not have any problems in other games or apps, only in DosBox...

Anyone have new insights/solutions for this behaviour?

Cheers and TIA
Klaus

did you allready try replacing the sdl.dll with a newer version ?

did you allready try replacing the sdl.dll with a newer version ?

YEAH - THAT'S IT!!

I've downloaded version 1.2.5.0 of SDL.DLL (220 kB) and CPU usage in windowed mode is ok now!
The one that came in the DosBox 0.63 package did not have a version number assigned to it in file properties (it is 349 kB)...

Thanks a million for your help Qbix 😀

Still have to test fullscreen modes other than surface rendering....

Cheers
Klaus

odd as dosbox uses 1.2.7
latest is 1.2.8

Have just downloaded 1.2.8 and this one works fine for me as well...

Seems like the SDL.DLL that came with DosBox is the only one that stresses my CPU in windowed mode.

Strange...

Klaus

http://www.libsdl.org/download-1.2.php

It might be related to the fact that the official SDL.DLL builds don't support DirectX hardware surfaces and that your problem only happens in hardware-acclerated modes.

I myself have a Radeon 9800 Pro with two monitors, and I get bad performance if I span some stuff like DOSBox across the two monitors, but I think it works fine if I make sure its only on one or the other.