ZBrushCentral

Importance of graphics card RAM for Zbrush?

ZBrush Usage Questions
#1

Since graphics cards again have more RAM I begin to wonder if there is a gain in performance for Zbrush users.

Tom´s hardware did a test with the new GeForce GTX 285 with 2GB ( http://www.tomshardware.com/reviews/gv-n285oc-2gi-gtx-285,2380.html ) where the test showed no real gain in gaming. However those worlds that are still using the same amount of polygons and textures which is probably optimized for not ever needing a 2GB card.

But how about when you use polygon meshes of millions of polygons and want to be able to get as much as possible on screen, to what degree is the RAM on the card a bottleneck? Or is that point so far far away that you should spend the money on more system RAM before that?

As you right now in the same price class you can get 512, 1024 or 2048 MB of VRAM depending on what model you want, what would be the best choice for a Zbrush artist?

Thanks for any answers on this one.

#2

You’d be better off investing more money into a very nice CPU and a good amount of fast RAM. ZBrush mainly utilizes those two more than GPU.

#3

Yes, I think so too, but it would feel a bit silly to buy a lot of other good parts and then need to upgrade the graphics cardbecause you need more ram, likewise it would feel silly to spend that extra bit just for more memory if it´s then never used.

I´m not that good at rendering techniques and memory usage, but I assume that the memory use of the graphics card will mainly use the memory as vertex memory as you usually only have one if any textures on the model while sculpting.

So this might be a very technical question but let me still rephrase it:

If you have a model that let say use 10 GB of the RAM, about how much memory would that model need to fit on a graphics card?

If it´s below 512 MB then I guess most people wont need to bother about these posts for a while, but otherwise it might be interesting to keep in mind when upgrading.

#4

The amount of video ram needed to display your image is minimal at best. If you think about it in dpi and document size then you can figure out about what you’re holding up.

zbrush is 72 dpi…well, always was before PaintStop. and your default document is under a 1k image. I’m not sure on the RAM side what that requires, but I know it’s next to nothing.

#5

Fast memory ram yes, lot of it not really, at least now. ZB is still a 32 bit application, so even on 64bit OS’s it won’t use more than 2GB.
Hopefully ZB4 will finally be a 64bit application ? :stuck_out_tongue:

#6

zbrush is a hybrid. It will use up to 4gb of ram if you’re running a 64bit OS. I’d say by the end of the year…or z4 release you’ll want as much as you can get though. same with CPU…and maybe GPU…but eh, we’ll see on that end.

#7

Look at this:

http://www.zbrushcentral.com/zbc/showthread.php?t=71

#8

I run Leopard 10.5.8 (so it’s a 64 bit OS), and through the activity monitor I have never seen ZBrush 3.2 use more than 2GB.

I don’t know if folks on WinXP 64bit have a different experience…