How much Ram on 32 bit System?

[smokey]

Hi,

I´ve heard several times that windows 32bit can only use 2Gb of Ram for a single process. Is this correct?
If yes, does it mean that there will not be a difference for fumefx in enlarging the ram from 3gb to the 4 gb border, when there are already 2 gb free?

[ddiener]

You're right.

(It is possible, that the overall systemperformance will be a little bit better with 4GB, but: ... )
...Fume will not really take profit of this. Because of Win32 Fume is limited to 2GB RAM. As soon as it needs more, it crashes.

[smokey]

Could fumefx 32 bit render *.fxd files that were calculated on fumefx 64 bit on a 64 bit system?

[Woody79]

i seem to remember this mentioned on CGFluids, i think you have to make sure your not exceeding the RAM limits of the 32 bit machine. for instance if you max out the full 16gb, you will need that ram to open the files up and render. so a 32bit machine would die. so if you are running massive amounts of ram, you may need a few machines to render it, also with a massive amount of ram. rif would know more on this. he has 16gb machines 8)

[Rif]

"Could fumefx 32 bit render *.fxd files that were calculated on fumefx 64 bit on a 64 bit system?"

The answer is Yes it can do that as fxd is external file , you just need to load it from the cache output on a new grid in you r 32 bit max and send it to your 32 bit farm that new file pointing to the caches that where calculated on 64 bit.. ..

Woody is right about the limitation of 32 bit os \ apps .. a 32 bit machine with 4 gig of ram and the 3gig switch on will swap over 2.5 gig or so from max if i remember right .. this is i think the worse setup personnally as i sa max8 craching alot over 2 gig even with the 3gig switch cause of the app itself not done for more or such..

Best setup is xp64 with max 9 64 bit .. Now in comperasion , if you run xp64 with max 8 sp3 , you will be better than xp32 bit with max 8 as now the os itself allows for ram allocation to be more than 2 gig per apps ..

After more infos from kresimir , i learned that its actually about 1 /3 of the Total Sim amount that you need to have to render a file.. witch means if you sim took 9 gig of ram to render on ur 64 bit , you should plan at the min 3 gig of ram from the render to be able to render that file .. Now 3 gig of ram means that it needs to be able to load the 3 gig , witch means xp64 + max 8 sp3 at the MInimum.. i would still suggest about half of the ram simed amount for render as you ll probably wanna render gi , Ao , render elements and extract the whole thing in passes or such ..

[Woody79]

1/3. thats interesting to know.

These sort of things need to officially noted somewhere i guess.

[smokey]

wow, thats a lot of nice information! thanks a lot!