When is 16MB not enough?

While testing Tonic Trouble with various cards, I discovered something I wasn’t quite expecting. Thinking about it now, I should have actually expected it – after all, it’s only logical – but for some reason I didn’t think of it at first. That is, the 16MB of onboard memory of the Voodoo 3, which I thought were good enough for everything, must have had an impact on some games.

In the previous post, I showed a screens comparison between the Savage 3D, with a mere 8MB of onboard memory but supporting AGP texturing, and the Voodoo 3, with a much better 16MB but no support for texturing via AGP. I’ll post it again here:

Savage 3D, with all available memory (17480KB). Very sharp, very nice. Runs okay, too.
Savage 3D (17MB of texture memory available)
Voodoo 3, no AGP texturing (8412KB, looks the same as 4096KB). The lower sharpness is likely due to the way the game renders internally, rather than the amount of texture memory used. Still, it's enough to make me reconsider using the Voodoo 3 as primary card.
Voodoo 3 (8MB of texture memory available)
Voodoo 3 (2MB of texture memory available)
Voodoo 3 (2MB of texture memory available).

So, it’s easy to see that the Savage screenshot has sharper textures than the Voodoo 3 at its best setting. This surprised me at first, because the game didn’t look like anything that required more than, say, 4MB of texture memory. I even thought that maybe it was a problem with the internal rendering of the Voodoo 3. But in the end, it makes sense that the amount of free memory must have had an impact. A test with the Matrox G400, a whole 32MB of memory included, shows the same results as the Savage 3D, albeit with far better performance (as expected).

This also gave me the answer to a question that came to me last year, when attempting to play the GOG version of Urban Chaos.

Game running on a Voodoo 3. But this is also how the game looks like when I'm playing the GOG version on my modern PC.
Game running on a Voodoo 3. But this is also how the game looks like when I’m playing the GOG version on my modern PC.
Game running on the G400. What a difference a few more megabytes can make.
Game running on the G400. What a difference a few more megabytes can make.

One thing is clear: the Voodoo 3 does not have quite enough memory to render textures at their best size, especially when higher screen resolutions are involved. In that case, the framebuffer takes away too much memory. The lack of AGP texturing means there’s no way around this, other than decreasing the resolution. The Savage 3D looks the same as the G400 screenshot (although obviously running a lot worse), so even with a mere 8MB of memory, of which almost 7MB are used for the framebuffer alone, AGP texturing still allows it to reach a result that is out of the Voodoo’s reach.

However, in this particular case, texture trashing might end up being a problem. The only way to test this would be to attempt with two cards of same specs, but one with 8MB (so that the textures are loaded almost entirely into system memory) and the other with 32MB, so that it won’t need AGP texturing at all. Unfortunately, such a card would be pretty hard to find. A Rage 128 Pro might do it, but it wouldn’t come cheap. I don’t even have one, nevermind two. It would be a lot easier if there were a way to limit the amount of video memory used by the system. I don’t think there is anything like that, though. At least not that I know of.

Another thing is clear, and that is, for some reason the GOG version thinks there’s some 16MB of memory on the graphics card. I assume this is due to how the game was modified to run on current systems. But other people said they get the higher quality textures instead. Who knows what’s going on behind the scenes then. It would be interesting to see what is it the game sees.

Advertisements

2 thoughts on “When is 16MB not enough?”

What says you?

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s