Different mixed of DDR2, will there be problems ?

[V3]

I've got a friend, she worked with Photoshop with large image file (about the size of two A4 @ 1200dpi). I noticed her PC was sluggish with heavy hdd access and Photoshop report poor efficiency of around 40%, even if I set Photoshop to use 100% of free memory.

Her system is A64X2 3800, Gigabyte mobo and 2x no brand 512 MB DDR2-533 and running Win XP32. I noticed there are two slots free, If I put in 2x 1GB Kingston DDR2-677 into the two free slots for total of 3GB, will there be any problem, like stability issue, etc ?

The manual said to go with the same type and brand thus the question.

I want for Photoshop to be able to use up the max of 2GB, it can allocate. While having another 1 GB for Windows and other small background apps. I could take out the two 512 and only have 2 GB total, but I think it would be really nice to have 3 GB total.

Thanks.

 

[Davros]

shouldnt see any probs
make sure you have them in the right slots so you get dual channels

 

[V3]

Thanks.

Currently the 512 occupied slot one and two. This is dual channel config for this mobo according to the manual.

Can I put the 1GB in slot three and four ? Or do I need to put the 1 GB is slot two and four or slot one and three ?

 

[Davros]

if slots 1+2 are the same channel and 3+4 are the same channel
then id put 1gb in slot 1, 1gb in slot 2, 512mb in slot 3 and 512kb in slot 4

 

[Kurt]

Back when I had an ASUS A7N8X-E Deluxe I couldn't get it to boot with 2x512MB + 2x1GB. Either pair worked fine by itself in dual channel mode. Not saying it's impossible, but largely dependent on your board and BIOS. Better check the manual or online for compatibility issues before bying the memory.

Correction. I just remembered, the ASUS worked fine with three sticks (2x512 + 1GB, had only three slots). It was a Gigabyte + A64 that didn't work.

 

[V3]

Well the good news, luckly this Gigabyte mobo, can take mixed RAM sticks, since It didn't have problem.

The bad news, the extra 2 GB of RAM did nothing to help the poor performance of Photoshop for her work.

Photoshop can only used 1.8 GB of memory, it used all and 10+ GB of Photoshop temp file. So I guess until there is a 64 bit version of Photoshop, there is really no hardware solution to this.

On another note, after the upgrade I drop the page file from 2 GB to 512 MB, she said sometime Windows low virtual memory warning pops up, did I set it too low ?

 

[Rainbow Man]

I see no reason why PS should only be able to use 1.8GB... It should be able to grab the max free amount; limited by the 32-bit barrier of course for older CPUs/32-bit OSes.

I put 3GB in my old PC with a 32-bit P4 main CPU just for fun and it works fine.
OPeace.

 

[V3]

Well, I think apps are limited to 2GB on 32 bit Windows XP. So Photoshop program itself would use some of that 2GB leaving only around 1.8 GB for your work. Basically 1.8 GB is the amount Photoshop show as being available on Photoshop prefrences menu.

Anyway CS4 will be 64 bit, I'm going to help her switch to Vista 64 and upgrade her memory to 8 GB (the limit of her mobo) when CS4 is out.

 

[BRiT]

Have you tried the /3G switch for XP? The default behavior of XP is to split the 4GB address between Apps and OS, each getting 2GB. With the switch, the OS is only given 1GB leaving upto 3GB for Apps. I'm not sure if the app has to be compiled with the large addressing flag [ IMAGE_FILE_LARGE_ADDRESS_AWARE ] or if they're able to be hacked to that to make use of the extra 1GB.

 

[V3]

Yeah, I read about the /3G switch for XP. I was afraid to try it since it wasn't my comp. How does it work ? I asked the Adobe support and they said it wouldn't make any different. The thing is the /3G swtch changes the allocation of the virtual memory, not the physical memory. So I assume Photoshop would still only be able to use the physical memory 1.8 GB it's coded for since Photoshop has its own virtual memory.

 

[Davros]

i know this doesnt really help but have you ever tried satori its a resolution independant graphics program
its really good when it comes to working with huge images eg: 40,000x40,000 pixels
there is a trial here
http://www.satoripaint.com/

 

[Rainbow Man]

How exactly woudl one invoke this /3G switch?

Sounds interesting but I'm cliueless on this opic.
Peace.

 

[BRiT]

It's part of your boot.ini file. From MS:

The virtual address space of processes and applications is still limited to 2 GB, unless the /3GB switch is used in the Boot.ini file. The following example shows how to add the /3GB parameter in the Boot.ini file to enable application memory tuning:

[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(2)\WINNT
[operating systems]
multi(0)disk(0)rdisk(0)partition(2)\WINNT="????" /3GB

Note: "????" in the previous example can be the programmatic name of any of the following operating system versions: