Better computer, worse performance

I'm really stumped. I recently got a new system at work that is better than my home system but when I run my game on it, the FPS drops from 80+ to less than 2. It really crawls.

Home system: Dell, PIII 933mhz, 32mb NVidia card, 128 MB Ram
Work system: Dell, PIV 2.4ghz, 64mb NVidia card, 256 MB Ram

Both systems have the DX9 SDK installed, both running Windows XP. The game uses DirectDraw from DirectX 7.

I've gone so far as to strip the code down to the bare minimum and add piece by piece to see what slowing it down. It seems to be only when I try to blit more than a few things to the screen. I can load all of my bitmap surfaces with no trouble. With them all loaded I can blit 2 or 3 items to the screen (all the tiles are the same size) with no slow down, but as soon as I increase the number of tiles drawn it starts to crawl.

I'm really stumped and about ready rewrite all my graphics code in OpenGL (which my OpenGL programs run fine on either system). Has anyone else ever experienced anything like this?

No, but I have had my DX startup code fail on one machine and work on another. Its these types of errors that give me a headache.

Maybe you should try to use the DirectX9 interfaces instead of the old DX7 ones. I realize this might be a pain in the rump since DirectDraw has been merged into D3D but there are still ways to do tile engines.

It could be that the hardware blitter (I'm assuming you are using it) has been significantly altered in the newer GeForce card to accomodate for something else. The newer card is going to optimize for 3D only so the 2D will suffer. Only guess would be that the hardware blitter has either been altered, removed (not likely since it would return an error), or corrupted in the driver on your newer system.

Note that if the hardware blitter has been removed from the new NVidia driver then DX will use the software equivalent which will cause a major slowdown. I cannot see this as being true though since NVidia uses a universal driver architecture. Theoretically if the blitter is there for the old driver, it should be there for the new one.

Sorry, just a guess. But it does sound as though you are using a software function instead of the hardware equivalent - which would cause a major slowdown. Perhaps you could use D3DSpy to track calls to the API to see which layer you are using - the HAL or the software emulator.

Bubba saying "driver" made me realize something. The driver that comes installed for Geforce cards after you install Windows sucks. The one that was on my computer after I installed WinXP (before I updated it) messed up on transparency. Go to the NVidia site and get the new driver for your computer at work. It's not digitally signed by Microsoft, but it works and is a lot better than the "official" one that MS approves. I could easily see that accounting for the difference in performance.

Thanks for the suggestions/replies, guys! I'm home for the evening now but I'll download the newest driver tomorrow.

blackrat, thanks a ton!!! That fixed it. I never considered upgrading the driver.

As for using DX9 I've been playing with DX9 and OpenGL and I much prefer OpenGL for 3D. My next game will be written in OpenGL, but since I've gotten so far on this one with DirectDraw I want to finish it, then maybe port it to OpenGL later.

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blackrat, thanks a ton!!! That fixed it. I never considered upgrading the driver.

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...and to Bubba for mentioning it might be the driver.

:D

Sorry, Bubba! I wrote it in a hurry while on break from work. Many, many thanks to BUBBA and blackrat.

:)

OpenGL is 3D heaven.