my imac is really slow. I would likee tp up upgrade the momeroy the current 8 GB to 16GB. I need your advise about how to do.

I haven't done a clean install of over 25 years. I do boot occasionally into Safe Mode according to How to use safe mode on your Mac and which:

• Verifies your startup disk and attempts to repair directory issues, if needed

• Deletes font caches, kernel cache, and other system cache files

I've found Ventura on my 2017 iMac to be the fastest I've experienced. I avoid at all costs any "cleaning", "optimizing", "speed-up", anti-virus or VPN apps. And I shut down at night which also cleans out system and app temporary and swap cases.

Your problem is almost 100% not a RAM issue. It is likely the hard drive. What you need with that computer is an external SSD and then install Mac OS onto it, set it as your boot drive and then boot the computer. Once you have done then you can put your data and apps on the external SSD.

There are 2 external SSD's I'd recommend.

1. OWC Mercury On The Go Pro (1TB model) and a OWC On the Pro Go Power Adapter OR A
2. https://eshop.macsales.com/item/OWC/S3D7P6G960/ and a SATA to USB adapter

Either will make your system considerably quicker. The top choice is a little cleaner to look at on your desk however either solution will improve the computer dramatically.

However, I'd also recommend that you do what OT recommends, posting an EtreCheck report so we can look to see if there are any other issues that you need to address.

Is your 2017 iMac a 21.5" or 27" model? Only the 27" model can have the memory upgraded by the user.

Actually, it's not memory that speeds up a Mac but a faster hard drive. Getting an SSD drive will speed up boot time, application and document opening time and saving time.

Memory will let you increase document processing time once they are opened and have more apps opened at one time without slowing down.

Download and run Etrecheck.  Copy and paste the results into your reply. Etrecheck is a diagnostic tool that was developed by one of the most respected users here in the ASC and recommended by Apple Support  to provide a snapshot of the system and help identify the more obvious culprits that can adversely affect a Mac's performance.

Copy the report

and use the Additional Text button to paste the report in your reply.

Then we can evaluate the report to see if we can determine the cause of the problem.

First what size iMac do you have and what is the model year? Next, why do you feel it needs a RAM upgrade?

We can help you however we are not mind readers. Apple has been making iMacs for about 23 years in hundreds of configurations. We also lost our last qualified mind reader the last time there was a lunar eclipse a night or so ago.

Yes a SSD is orders of magnitude faster than your 5400 RPM hard drive. That is what is making your computer so slow. Adding RAM will not make it faster only adding a SSD will. Adding RAM to your machine requires a 100% disassembly which must be done by an Apple Authorized Service Provider and as mentioned will do nothing to improve performance on your current computer.

You other option is selling it and buying yourself a new 24" iMac, all of them come with SSDs and are extremely quick. If you do decide to go that route, get one with a minimum of 16GB of RAM (it cannot be upgraded after the fact) and a 1TB SSD. These also come up on Apple's refurbished store so that is an option if you want to save some money. Apple refurbished Macs have no downside, they are identical to new, come with the same 1 year warranty as new, are eligible for AppleCare and save hundreds of $$.

Your EtreCheck report indicates nothing is wrong. What you did was bought the cheapest iMac available which is only designed to do light web surfing and get e-mail and then you installed professional grade applications (Adobe apps) and expect the machine to be quick. Unfortunately the only things to do are get the SSD or replace with a newer machine.

With your iMac being a 2017, it might be time to do a clean install. If you have a way to use Time Machine to back up your Mac to an external, then you do a clean install of the MacOS. Keep in mind that every time you open an app, you are created a cache for that App, and depending on the App, that cache can be massive (for example a Safari Cache is typically massive with your web history in it).

If you don't want to go the clean install route (which includes deleting everything, and reinstalling the MacOS) then I would recommend that you look for a good cache cleaning App which will wipe out all the extra junk on your hard drive.

The iMac you purchased was the slowest one that Apple offered at the time of purchase: 8 GB RAM and a 5400 rpm hard drive.

Your Adobe software is crashing frequently. Make sure you have the latest version and it's compatible with your system.

If you're considering an external SSD to boot and run from as rkaufmann87 suggested look at those offered by OWC (MacSales.com). The are considered my many as the premier supplier of 3rd party hardware for Macs. Contact their Customer Support to see what they recommend to match your Mac's capabilities, your workflow and your budget.

If you don't want to go the clean install route (which includes deleting everything, and reinstalling the MacOS) then I would recommend that you look for a good cache cleaning App which will wipe out all the extra junk on your hard drive.

FYI: The macOS has done self-cleaning automatically since the onset of OSX 20+ years ago. No third-party cleaning apps are ever needed.

It’s been my experience that a Mac a few years old does start getting bogged down by constant updates not only to the OS but also the Apps. Doing a clean install wipes all the caches out and all the older files.

This is the bottom-end iMac model, and with too little memory and with too-slow storage.

Here is why performance is a problem: Why is my hard disk drive iMac so slow? - Apple Community

Please run Etrcheck and post the results as I described above.