How much will going beyond 6 GB of RAM help PS CS4? Mac, so no 64-bit

[Dan Wells]

I'm using extremely large images in CS4 (Nikon D3x images, sometimes multi-layered or upsized to print as much as 24x36 inches), on a presently 6 GB Mac Pro. The D3x images start life as 140 MB TIFFs, but can go to the printer as large as 1 GB or more... Assuming that I'm not running anything else major along with Photoshop (I shut down Photoshop when I open Capture One, and vice versa), how much will more RAM help? I know that PS can only use slightly less than 4 GB directly, but it plays some trick using additional RAM as scratch disk to get around that. How much RAM can it use that way? Does 12 GB make sense (I have 4 512 MB FBDIMMs, plus 4 1 GBs, so replacing the 512s with 2 GB modules would yield 12 GB)? Would 8 GB be as good as 12 (it's little enough cheaper that I might go to 12, just so I can keep Capture One open with Photoshop)? Should I go all the way to the maximum capacity of 16?

                                             -Dan

[Anthony R]

More Ram never hurts, but there is more to it than that. I run 12 gigs on a 2x2.8 Quad-Core Intel Xeon but it's raided to 7200 rpm drives.

[bill t.]

On my CS4 64bit PC with 8gb ram I was just working on a file that reports "Doc: 1.63G/3.5G". That's a 500+ megapixel, 8bits/channel stitch with 5 adjustment layers.  At that point most CS4 functions like basic adjustment layers still work very fast.  Some of the more intensive filters like "Smart Sharpen" will start to invoke disc buffering that can take a about a minute to complete.  Huge improvement over the old 32bit system.  Somewhere beyond that file size the awful disc buffering starts in earnest, ouch.

8gb would probably be OK for 24mp, 16 bits unless your were into a lot of fancy layering.

I am definitely going for more RAM soon.  Those wanting to take PC's over the 8gb point should look at the new P45 chipset motherboards.

[johnchoy]

how much will more RAM help? I know that PS can only use slightly less than 4 GB directly

No, It's only for 32 bit  CS4. 64 bit Cs4 can use as much RAM as you can fit into your computer.

I suggest go the maximum way

[Farmer]

The OP is using a Mac and OS X - therefore PS is only available as a 32bit app for him.

If minimising other system usage, there will be a very minimal benefit to any extra RAM at this point.

[Anthony R]

The OP is using a Mac and OS X - therefore PS is only available as a 32bit app for him.

If minimising other system usage, there will be a very minimal benefit to any extra RAM at this point.

This is untrue. OP disregard.

Best to do your research on a forum that is specific to computers and/or Mac and not on a photography forum. If you wish to do your research in this medium and pursuit, getdpi.com has some valid, interesting and possibly enlightening information/threads.

[Farmer]

This is untrue. OP disregard.

Best to do your research on a forum that is specific to computers and/or Mac and not on a photography forum. If you wish to do your research in this medium and pursuit, getdpi.com has some valid, interesting and possibly enlightening information/threads.

What part is untrue?  The Macs at work show a significantly diminishing return for CS4 over 6GB RAM.  That's a fact.  CS4 on a Mac is 32bit only.  That's a fact.  So no part of that is untrue.  More than 6GB won't show a significant benefit for running CS4 under OS X.  That's real world.

The OP stated that rastered files being sent to print are about 1GB in size from 140MB TIFFs.  How exactly do you propose that more than 6GB of RAM is going to significantly speed up the OP's operations?

[johnchoy]

The OP is using a Mac and OS X - therefore PS is only available as a 32bit app for him.

If minimising other system usage, there will be a very minimal benefit to any extra RAM at this point.

Sorry I forget the mac osx/ CS4 factor. But what about bootcamp running windows, though I'm not sure if bootcamp support 64bit windows.

[joergen geerds]

I'm using extremely large images in CS4 (Nikon D3x images, sometimes multi-layered or upsized to print as much as 24x36 inches), on a presently 6 GB Mac Pro. The D3x images start life as 140 MB TIFFs, but can go to the printer as large as 1 GB or more... Assuming that I'm not running anything else major along with Photoshop (I shut down Photoshop when I open Capture One, and vice versa), how much will more RAM help? I know that PS can only use slightly less than 4 GB directly, but it plays some trick using additional RAM as scratch disk to get around that. How much RAM can it use that way? Does 12 GB make sense (I have 4 512 MB FBDIMMs, plus 4 1 GBs, so replacing the 512s with 2 GB modules would yield 12 GB)? Would 8 GB be as good as 12 (it's little enough cheaper that I might go to 12, just so I can keep Capture One open with Photoshop)? Should I go all the way to the maximum capacity of 16?

-Dan

Hi Dan,

I think you will see the most impact if you invest in a RAID setup for your PS scratch... PS CS4 under OSX can use the RAM above 3GB (you have set PS memory usage to 80-100%?) as cache before it starts writing to the scratch disks. so, buying 3 cheap 500GB samsung F1 or faster disks really helps a lot, the additional ram will only help marginally. if you really would like to build a speed daemon, get 1-2 raid cards, and get 8 64GB SATA solid state disks (rated at 90mb/s write, 150MB/s read, each about $100) (the disks are so small, you can put 4 of them in one drive bay i think). PS CS5 will be 64bit, and then it will use all the ram you have, but that is at least 12 months into the future i would say.

the other thing that puzzled me are your file sizes... how do you get them to 1GB for printing? my 120x60in prints are a little under 2GB when they go to a lightjet, I really can't see how you blow up a 24mpx to 1GB, even with 16bit and layers (the photoshop file yes, but the print file?).

[Dan Wells]

Hi Dan,

I think you will see the most impact if you invest in a RAID setup for your PS scratch... PS CS4 under OSX can use the RAM above 3GB (you have set PS memory usage to 80-100%?) as cache before it starts writing to the scratch disks. so, buying 3 cheap 500GB samsung F1 or faster disks really helps a lot, the additional ram will only help marginally. if you really would like to build a speed daemon, get 1-2 raid cards, and get 8 64GB SATA solid state disks (rated at 90mb/s write, 150MB/s read, each about $100) (the disks are so small, you can put 4 of them in one drive bay i think). PS CS5 will be 64bit, and then it will use all the ram you have, but that is at least 12 months into the future i would say.

the other thing that puzzled me are your file sizes... how do you get them to 1GB for printing? my 120x60in prints are a little under 2GB when they go to a lightjet, I really can't see how you blow up a 24mpx to 1GB, even with 16bit and layers (the photoshop file yes, but the print file?).

The iPF6100 wants 600 dpi input from the PS plugin, and I find that a genuine fractals uprez to give it that input is better than feeding it a ~200 dpi file without uprezzing and letting it scale the file however it chooses.

                                               -Dan