Why is my brand new iMac so slow?

Question

Hi,
I bought my iMac about four months ago. Never had a Mac before and I'd been looking foreward to it
for a long time!
Specs: iMac 27" | OS X 10.6.8 | quad core | 2.7GHz | 4 gig ram | 1 TB disk | 1333 MHz | DDR3
Very early it striked me how slow this machine was! Starting and rebooting is insanely quick, but
that's about it! I work in Photoshop, and it is just horrible. It crashes all the time! I am used to work
with several layers, I can't do that here. Because it's sooo slow...
I also work in a 3D program called ArchiCad and this is even worse! I've had to teach myself a
slower workflow to prevent it from crashing. I hate it...
If both Photoshop and ArchiCad is open at the same time, the Mac crashes VERY fast. I have to force quit app's
and reboot the Mac often. Sometimes several times in one day.
I see this little circus wheel all the time and it's driving me nuts!
Sometimes the Mac just crashes without having lots of apps open. I might have a couple of browsers open,
a word document, finder and a priview. And it crashes!
And I have to do the eternal job of force quitting and trying to tell the Mac to reboot. This often takes a while.
The Mac is full of small problems also.
- I have to install the magic mouse all the time! It just gets lost and I have to use my track pad
  to search for it. Even though the batteries are new. Sometimes this only happends once every
   second week, sometimes it happens 15 times a' day.
- Sometimes I can flip between pages in web browsers by swiping with the mouse, sometimes I can't.
  Sometimes I can do this when working with folders, sometimes I can't.
- I often have problems with Java.
- The web browser Opera crashes all the time. Can't use it.
- Sometimes, videos from f.eks youtube can't play.
- Just opening a photo in preview can take 10 seconds! Not allways, but sometimes.
- Using cover flow with images is useless. It uses so much time to preview the photos with good quality.
You might wonder, what have this dude done to his Mac?
I have installed Photoshop, ArchiCad, Chrome, Opera and a small app for browsing an old iPod touch.
That's it!
Since I'm a photographer I've also put a lot of photos here, but not more than perfaps 100GB. Max!
I am very, very carefull with what kind of websites I visit. I never visit a website I don't trust.
I don't download anything (movies, games etc). Everything I have is original. No pirate.
So I brought it wth me to my local apple store. They thought it was a problem with the disc.
After being without the Mac for a week they told me nothing was wrong with it. It was perfect they said!
My jaw dropped all the way to the floor.
All they could say was that I could format and reinstall the intire system and/or upgrade to 8BG ram.
Do you guys think this will help? Why should I reinstall? I can't understand how I could've screeved the system up!
And really? I should use MORE money and upgrade to 8gb Ram? My previous 2gb Ram PC was so much faster! Is this necessary?
I hope someone can give me any advice.
I feel lost. This is by far the worst purchase I've ever done. I hate my Mac...

Answer 1

Well,
To start Dan, you are using quite a few CPU, GPU, RAM and HD intensive apps.
4 GBs of RAM isn,t going to cut it. 8 GBs isn't going to cut it! Not at all! 4 GBs Of RAM is the base (read minimal ) RAM the iMac model you bought comes with. It doesn't mean it's enough to run lots of Applications. Epecially processor intense applications you're trying to run!
Every re-iteration of OS X uses more and more CPU, GPU, RAM and HD resources.
OS X, BY ITSELF, needs between 2-4 GBs of RAM just to do its things smoothly.
Using Photoshop alone needs oodles of CPU, GPU, RAM and HD space for scratch disks.
If you are a seasoned Photoshop/Adobe user, you should already know this fact!
ArchiCad is another, CPU, GPU and RAM heavy app.
You have various browsers, email, word documents open simultaneously? Really?
More than one web browser open? Web Browsers also eat up lots CPU and GPU cycles and RAM!
The thing that eats up CPU, GPU and RAM cycles with web browsers is Adobe Flash and to some extent Java.
You're trying to run all these thing on very little to no RAM horsepower!!!
You're asking your iMac to run all these heavy processing apps with no additonal RAM available to do so.
As you've discovered, this is not working.
You're probably getting a lot of page in/outs and virtual memory swapping between real RAM and the hard drive.
You need to install, AT THE VERY LEAST, 12 GBs of RAM! I would just install 16 GBs of RAM and be done.
Your iMac can take up to 32 GBs of RAM, but this, I think maybe overkill. Try your system with 16 GBs first.
I have a 2009 27 inch iMac with 16 GBs of RAM running CAD and Adobe CS 3 and Blender 3D and other processor intensive apps with very little issues.
Buy reliable RAM from online sellers Crucial memory or OWC.
As wise advice from me, if you want to experience a smooth and productive Mac experience, do not upgrade your iMac to 10.7 or 10.8.
10.6.8 Snow Leopard is the last "real" version of the previous Mac OS X versions that many of us still love and use. Newer versions of the OS, basically, still have many issues and turn your iMac into a giant iPod, iPHone or iPad., Instead  of being a fully customizable and reliable OS.
The magic mouse is really a crppy mouse to use with drawing and painting applications like we both use.
Ditch it and purchase either the old RF style Mac compatible wireless laser mice or purchase a wired mouse.
These mice are more accurate pointing and tracking devices.
Look at Mac compatible mice models from Microsoft, Logitech, Kensington or Apple
The battery life of the magic mouse is just poor, also.  Its tracking is poor for fine mouse movements, too!
Does your wireless trackpad work any better? Is it better on baterries? Do you get fine control using it?
If the trackpad is better, than just ditch the magic mouse all together.
If the trackpad give you trouble, too, ditch it for a more accurate mouse, trackball or trackpad from another manufacturer other than Apple. Again, Mac compatible trackpads from Microsoft, Logitech and Kensington.