Hi and welcome to the forum
Is your OS 32 or 64bit? If 32bit then you'll know that Photoshop can't access more than 3Gb RAM, and CS5 is a bit of a RAM hog. You can test by going Edit > Purge > All and seeing of that gets things moving again. If that does help, then maybe look at Windows 7 Pro and more RAM.
Having said that, my laptop with Win 7 64bit and 4Gb works passably well with CS5, but only just.
If the Purge helps, then perhaps set up an action to make a quick operation, but you loose your history, and undo states of course.
It's the 32bit version. I know it can't access more than 3.5 Gb but I don't think my ram is the issue. I can open a small file and after some time, there is a delay for every action.
Also, purge does nothing to fix my problem. It's something PS does the moment I click on the canvas.
I have new information regarding my issue. It happens each time I start to work. This delay appears only when I click on the canvas to perform an action. It's most visible when I try to use the Hand tool to pan the canvas, I click to move but there's a slight delay before the actual screen result. This delay increases in time, even though I don't work and just leave Photoshop alone. After a period of time this delay disappears and everything is back to normal.
Also, if a try to pan the canvas using the scroll wheel everything is fine. Also, no problems when I try to zoom in or out. I've tried different scratch disk locations, different performance settings with no success. I've tried to close third party applications, in case something would have interfered with PS, and nothing. Is there a way to monitor the mouse input to see what happens when I click the canvas to execute an action ?
After paying almost double the US price for the same product, one would expect an outstanding support for that unjustified amount of money. How naive of me to think that way.
This concludes my Adobe experience. Thanks anyway.
Could be also a graphics card problem, maybe your spec are to low. I seem to remember that CS5 has been optimized and uses the graphics cad memory in CS3 this was not the case.
And 4gig of RAM in your setup real is not enough, you need to know that your system is also using a important part of the 4 gig just to run the system. So maybe there is only 2gig for Photoshop to use. And when you do something in Photoshop it will always make a complete copy of you file in memory to be abele to use history this means if you have set your prefs to keep 20 levels of history it will copy 20 times you complete file in memory when doing 20 adjustments on your file.
Hello! the graphic card does not seem to be a low end one...
could you try disabling OpenGL in the preferences, to see if it is related to the card or its drivers?
Also, what is your current driver for the graphic card?
Remember that this is a user to user forum... You are not adressing Adobe.
Can I get a refund for cs5 or can I exchange it for cs3 ?
You're really asking that question in the wrong place - this is a user to user help forum. We're just users like you. I do know that you can no longer buy Photoshop CS3 from Adobe though. They only sell the latest release.
I will say this, however: You really should try to figure out just what's wrong and fix it. Reverting to an outdated version of Photoshop just isn't a good approach, and lots and lots of people really are running the latest release of Photoshop with good results.
In my opinion, choosing to run an outdated operating system on your modern computer was your first step down a wrong road. What are you really trying to accomplish by avoiding modern software? You can't live in the past forever.