Home Forums Hardware Mac Desktops & Notebooks Opinion on extra Ram

I got the new 27" imac a year ago. It came with 4GB Ram.
The sales guy said it should be fine for what I'm doing.
Most intensive app I have is CS5 PS.

I remember years ago an Apple tech said if you buy more ram than you need it's like dust sitting on a shelf - waste.

But in Bridge recently, I got fed up with the 2 second delay to see large previews from the thumbnail pane, so I posted on the Adobe forum.

Based on a recommendation there I quadrupled my ram to 16 GB.
But I don't think it fixed that issue! And I'm not sure I notice anything different really anywhere else as far as seeing less beach-balls etc.
What do you all think?

Photoshop is one of the biggest consumers of RAM there is. If you do a lot of Photoshop work, no matter how much RAM you have, it's never enough.

However, having said that:

The delay you see with viewing large thumbnails in Bridge isn't related to RAM. It's related to the speed of your hard disk. The previews are generated by looking at the image on the hard disk; since a hard disk is literally thousands of times slower than RAM, you'll get delays no matter what. You will see a performance boost if you replace the hard drive with a faster model. You'll see a BIG performance boost if you replace the hard drive with a SSD.

It used to be true, in the ld days of OS 9 and before, that if you had more RAM than you were using, it was wasted money. The Mac used to use a static memory allocation scheme--you had a pool of RAM, you told each program how much RAM to use,and RAM that was not being used just sat there.

With OS X, the operating system will use unallocated RAM for buffers and such, so it is being used. You might not notice a huge performance boost, especially because some of the boost is masked by having a slow hard drive, but it is there.

thanks Tacit,
just spoke with tech guy at Crucial and he concurred with what you said in that it's more an issue of the hard drive. Can't wait to have 3TB SSD externals for that! which are cheap.

Hence I'm returning this Ram. I'm not doing video.

External how? FW800 can't keep up with a decent 7200rpm hdd. Don't waste your money on an SSD if you can't find a fast way to attach it. (such as internally) Also, where exactly are you finding 'cheap' 3TB SSDs?

Exactly, I'm returning the Ram, and not thinking about these issues anymore. Will see the speed bump down the road when I upgrade the computer.