How to change screen size for games

[JCAP]

Hi, I'm terribly sorry if this is in the wrong category, I'm new here and I just want some help with my problem.

I use Windows 8 and I want to play a game called Duel Savior. Due to compability problems with DirectX, the game doesn't work on Windows 8, so I installed a virtual machine with Windows XP.

I already installed guest addition so in normal using, the screen size adapts easily to the size of the window.

Problem is when I run the game. Because the game runs in 800x600 resolution, virtualbox renders a small image (my screen is 1920x1080) and I can't find a way to expand it.

I can't change the game resolution in-game, so I have to force virtualbox to expand it. Is there a way to do it?

Thanks in advance.

[Perryg]

Use scaled mode while playing the game. ( toggle = Host+C )

[JCAP]

Use scaled mode while playing the game. ( toggle = Host+C )

Thanks for the reply, however, it doesn't work.

The image adapts to the size of the window, but it doesn't render properly. It will either render only one frame and won't render anymore frames, or if I change the size of the window, it will render normally in a small portion in the up-left corner while the rest of the window stays in the previous rendered frame.
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