I’ve a couple of questions regarding the RAM usage of ZBrush.
Does ZBrush use the 3GB RAM that is provided when the /3GB switch is set in the boot.ini?
If so, would that raise the maximal possible polycount per Mesh? How much (in%)?
Does ZBrush save the setting for MaxPolyperMesh somewhere that it sets on its first start based on your system? And does ZBrush refer to this first setting somehow - even when the system specs changed in the meantime?
Boa
When you right click on My Computer and choose Properties, you will see how much RAM is available in your system. In order for ZBrush to make use of it, you need to set the Preferences>Mem>Compact Mem setting to be a little below that value. Be sure to then save your preferences.
The MaxPolyPerMesh value is set automatically by ZBrush based on your system. There’s no need for you to change it unless you wish to push your system harder. You should not set it to anything over double the default value.
When I installed ZBrush it gave me - if I remember correctly - 3 million as the MaxPolyperMesh value. I adjusted the value and I could work with meshes up to 6 million.
Sometime after the installation of ZBrush I configured my boot.ini with the /3GB switch. My guess was that this should up the amount for MaxPolys. I adjusted the value again to 8 - 9 - 10 millions but got a crash when trying to load tools bigger than 6 million polys (as described in this thread:
Crash while loading tool bigger than 6 Mio Polys
Therefore my question: Does ZBrush recognize more than 2 GB RAM?
I think my system is “there to be pushed”.
Again the specs:
Dual Opteron 248, 2.2 GHz on a TYAN Thunder K8W (S2885) with newest drivers and Bios(version 2.02)
4GB DDR-RAM PC-3200 ECC reg. Kingston (8x512)
PNY QuadroFX 3000
Storage: 4x Maxtor DiamondMax Plus 9 160GB SATA
RAID: Promise S150 SX 0,0+1,1 Controller
MS Windows XP Professional SP1
How can I change this configuration so that it is able to deal with meshes of 8 to 10 million polys?
Boa
Have you checked your system properties to see how much RAM Windows is saying you have available? It does no good to modify your ini files if the changes that you make are not being recognized by the operating system. (Case in point: Windows ME refused to recognize any RAM over 512 MB. You could put in a GB if you wanted and see it recognized by your BIOS during boot, but Windows was still only going to make 512 of it available to you. I know that you’re not running ME, but this situation may be similar.)
Also, have you adjusted your Mem>Compact Mem setting? This setting tells ZBrush how much of your available memory to use. You could have 8 GB of RAM in your system, but if this setting is not changed then ZBrush will only use the default amount of 256 KB.
One last thing that I recommend doing: Rename your UICustom.cfg file to UICustom.bak. Restart ZBrush. What does it say for the MaxPolyPerMesh value? That setting will be thre recommended max based upon how much RAM Windows is making available to ZBrush. You should not set this value to more than twice the recommended amount.
Regarding the maximum RAM that ZBrush can use, the answer is 4 GB.
Thanks Matthew for your fast reply.
Yes, I’ve checked the available RAM. It says 3.18 GB. I’m on XP Pro. And I’ve seen 3ds Max using more than 2 GB. So I know that the /3GB switch is working. The Mem setting is also adjusted to 3000 …
I did the test you recommended. Starting with a “fresh” ZBrush (renamed UICustom.cfg file to UICustom.bak)gives only 256 MB and 3 million PolysPerMesh. No other programm was open at the same time.
Can it be a XP Pro - ZBrush communication problem? How can I say to Windows to allocate 3 GB to ZBrush?
Hope you can help me,
Boa
Hi Matthew,
this is to bring this issue to your attention again. ZBrush obviously does not recognize my system’s RAM when I see the settings ind the “fresh” ZBrush.
What can I do to get the performance/MaxPolyPerMesh from ZBrush that 3GB should allow?
Boa
Any ideas what I could do? Can’t believe that 3 GB available RAM does not result in more possible PolyPerMesh.
Why is it that you have to save the high poly mesh? Can’t you just save out a lower level of the model, with the displacement from the higher level model, and recreate it later? That’s what I would do if I was having issues reopening a model with a high polycount. Zbrush is pretty good at recreating the geometry from displacements.
It’s just a suggestion, maybe that would work?
Why is it that you have to save the high poly mesh? Can’t you just save out a lower level of the model, with the displacement from the higher level model, and recreate it later?
Thank you for your suggestion. But I’m afraid that this will not work. I need to detail the mesh further. And making the displacement in ZBrush look the same as the original high poly mesh means subdividing to the same level.
I think there is something fundamentaly wrong with the communication between ZBrush and my system which I would like to fix. I also get occassional “out of memory” messages with lower count polys (around 3 mio). ZBrush doesn’t crash on those messages and executes the commands. But I think this as an other indication that there is something wrong if you take the amount of 3GB available RAM in consideration.
So: Still looking for ideas how to improve/alter the Zbrush to system communication. Matthew?
Hi Matthew,
I don’t know whether you have overlooked my question or whether there is just nothing I can do …
Still hoping … and I’m curious about the “normal” MeshPerPolyCount on systems with 3 GB available RAM and a Compact Mem setting of 3000.
Boa
isnt the limit for zbrush 8 million polygon models?
isnt the limit for zbrush 8 million polygon models?
… and I was hoping that I can use that much … I thought that 3GB RAM should be enough. But got only crashes on tools bigger than 6 million polygons. 