16GB for blender

I’m going to be throwing another 8GB into my mac pro next week so it will be interesting to see what the extra memory will do for blender… once the mac port supports 64bit addressing. Anyone here have more than 8GB in their 64bit environment?

Nothing? AFAIK Blender only supports 1.5GiB ram as is (or is this outdated already?) unless you use an adapted graphicall.org build with 4GiB support. Well for intel based platforms at least.

well the question at this time is more or less directed to 64bit platforms. I’m sure in a 64bit Linux and windows can use more than 4gb. My apologies if that looked a little consing.

I perfectly understood you the first time :D. 64Bit OSs can easily address >4GiB. But it´s not a matter of what the OS supports or is able to address, its a matter what blender actually uses/can adress and some time back i read somewhere that blender uses only up to 1.5GiB. Which would be odd, maybe someone with some blender code insight can proof me wrong pls :slight_smile:

Just found some info again.
The 1.5GiB limitation is
a) for 32 bit
b) for windows

Its the matter, that windows only allows a single thread to use 1.5GiB memory. There´s a workaround.
Well, then i am looking forward to your reports on what the vast amount of memory got you :slight_smile:

Blender on a 64 bit OS(Linux at lest) can easely support more than 4 gig of ram, try opening some of the BBB production files if you want proof;)

A 32 bit OS is actually capable of addressing 4~GB of ram, the 1.5 gig limit is a windows bug, there is no such problem on Linux

Well, if you get it working using 16GB, I am officially jealous.

well. a 32bit OS can use 3.5 GiB ram. eventhough it could adress 2^32bit (4GiB), there is the memory hole (PCI hole) which is created by the bios to keep room for the pci device memory thingy. (dunnow the correct english term :)) Windows is not using this memory unless you force it too, but then crashes are scheduled. You could use PAE to enable the 36bit adressing under win32 to use up to 32 gig ram (have fun buying the modules) but still the memory hole exists. AFAIR the hole is 500MiB to 1.5GiB.

In linux i am actually not sure, but as we all know linux got the better memory managment, so i guess linux32 can use up all 4GiB easily;)

with 64bit there would be theoretically 1^64bit = 1EiB (1.073.741.824GiB) memory possible, but all actual intel and amd chips use max,40 bit memory adressing atm.
the Mac we are talking about is a PPC platform or is it intel based? anyone can tell me what the memory adressing range of it is?

Still i am intrested too in what advantages or speedgains you´ll get in blender with more memory… beside more room for phys, liquid simulations and stuff.
I am not sure yet if i should get 4, 8, or 16GiB for my new puter… well 16 is actually too expensive ATM. damn 4GiB modules.

You can create 64bit builds of Blender for Windows these days. Genscher has been working on compiling all our dependencies for that, as well as making sure our sourcecode is 64bit compatible. I’m not certain how much is still left, but I have understood that most of our code is now ok.

With ultimate, business and enterprise, you should be able to address +128GB, as long as your hardware supports it.


Unless you are multi tasking with some pretty high RAM programs, I don’t really see the point. If you can store a gazillion particles and polys in your RAM that doesn’t mean your CPU and graphics card will be able to process and display them at anything other than .0001 fps.

During editing you may not need the gazillion particles (some nifty representation techniques and symbols could be used instead, LOD, etc), but it would be nice to actually see them in a final render.


For improving blender speed you rather buy a better 3d videocard with more 3d processing units.

Memory it is not so important neither on Windows or Linux , Linux has a memory management copy-cat from Windows NT … modified not so much , rather to topic Memory include swap so when you have 8 gb memory and 16 gb swap you got 24 gb accessible.

All operating systems work in that way , only if you force them to not use the swap and use only the hardware memory (this will make your pc lag all the way up , or crash cause when you are at the limit of your physical memory then you`ll se the need of the swap…)

So better stay with 4 gb and try to upgrade the video card , cause blender poly are rendered by the video card.

I have 2 gb memory and a junk of Nvidia 6600 and belive me , memory it is ok but the video card is dumb like hell even in WOW.

And difference from 32 to 64 it is not much , not to noticeable if you have a buggy video card.

So first for any system for 3d graphic are - A good processor Amd-Intel dosen`t matter to much but for laptops AMD- small price Intel - big price but less cpu heat , - A very good video card Ati performs better tha Nvidia at rendering but has bugs … in general Nvidia is better supported.

And if you are really smart you cand do things even with low profile pc ,maybe you wanna use sculpt intesively … not wanna play with patches and topology

the 1.5 GB ram limit is only in windows 32bit… though it can be bypassed so
see this link.
Blender 1.5GB memory limitation explained (by mpan3)

and yes…i’ll be looking forward to your experiences with using 16GB of ram with blender :smiley:

i’m on a turion 64x2, 3G ram… but still using 32bit OS (ubuntu hardy mainly)… i have a 64bit livecd,but not really sure if i wanted a 64bit OS, since i won’t be able to open my 64bit blends on 32bit blender…(is that right? or is the speed advantage worth it?)

Wow :eek:. 16 gigs of RAM!!

I’d love to see some world class fluid sims with that kind of power to work with. I’ve recently got “Bounce, Tumble and Splash”, and to create high resolution fluid sims you need upwards of 13Gb of RAM. As far as I can tell, there are work-arounds for many of the memory limitations, but some in-depth processes such as fluids and complex high-res scenes with mirrors and ray-tracing quite simply need the RAM. High RAM would not just speed things up but would make things possible that otherwise would be too demanding.

It is a specialised area though so maybe some of the other options that people have suggested would be better. Still, if you have the means to get so much RAM and want to experiment then I’m definately looking forward to the results :).

“I have 2 gb memory and a junk of Nvidia 6600”

Same! Although looking to go up to 4 gb or ram, hopefully tomorrow. Mainly for editing really large photoshop files though. The ram will help with high end displacement mapping and such if I need it though.

Well, “the more memory you have, the less likely it is that your system will do any virtual-memory swapping.”

Regardless of how much RAM is devoted to the Blender process at any particular time, well, “chips are cheap now.” And “chips” are just as fast as the CPU. The hard drive is not. Whether or not Blender uses all that RAM, OS/X certainly will.