Slow slow MB pro. Clean install SL or Clean install Lion?

I decided to do a clean install of hte whole system, and then recover my documents and some apps from my Time Machine backup.

I don't think you've thought this through. If the problem exists on your Mac and you've backed it up with Time Machine, restoring from Time Machine may very well bring back the problem, since you don't know what it is at this point. You culd find yourself back at the same point you are now.

Let's hold off on that idea until we know what the problem is and how to solve it.

I would suggest you download and run Applejack. You startup by pressing Command-S at startup until you see white on black text, then type 'applejack AUTO' and let it run through everything and then reboot. Then you can see if the problem continues, or to what extend. It may take more than one reboot to determine if the problem is still there.

Since I am gonna erase the whole HD, should I just install OS Lion or re-install SL?

Don't need to erase your hard drive; there's nothing wrong with it. You will need to reinstall Snow Leopard, since it's required before you could upgrade to Lion. But upgrading to Lion won't help you, it will only make things slower and increase the needed resources to run your Mac.

If I install Lion, can I choose which software and document to recover from my SL Time Machine backup later?

I'm guessing the answer is 'No', but since I don't use Time Machine, I can't be certain. I do know that Time Machine has been dropped as of Mac OS X Lion.

What are you using VLC to play? What other applications are running when you experience the apparent slowdown? How much RAM do you have on your Mac; what's the capacity of your hard drive and how much free space is left?

Seems to me your disk is dying.

Hi Kurt, what do you mean "I do know that Time Machine has been dropped as of Mac OS X Lion". ?

Lex

I mean that if the OP is/was planning to use Time Machine for backups with Lion, it's not possible.

We are off/topic but I do not understand you: I have upgraded from SL in december; all my TM's from before and after are available.

Yes, you had TM backups in Snow Leopard, which Lion will recognize. But Lion has dropped all support for Time Machine using third-party NAS drives. So unless you have an Apple Time Machine drive with a backup prior to Lion, there's no support for backing up using that in Lion.

Ahhh, now I understand. It is still in the Lion page at the Apple sites as a built-in app, but the NAS support is "gone". THX. I use TC, but I also have clones and other backups. Lex.

goitaca-ce wrote: I have 4 MB ram

No, you have 4 GB of RAM. So, here's some things you should try:

• If you have your Time Machine backup drive connected, disconnect it and restart your Mac to see if the startup speed or anything else improves.

• In Disk Utility, select your hard disk in the list of disks and volumes. Look at the bottom of the window for the S.M.A.R.T. Status. If it's green, that's good; if it's red, that means your drive is about to fail and you need to get all your data off it ASAP and then securely erase it with Disk Utility.

No, we want to find out if Time Machine is slowing down the startup process, as well as causing your problems viewing videos in VLC or anything else. That's why you want to disconnect the Time Machine drive and boot from the Mac hard drive itself. If the slowdown goes away, then that's the problem.

At the same time, just to be sure, you want to use Disk Utility to check the S.M.A.R.T. status of your Mac's hard drive: green is good, red is bad.

You should only erase and reformat the drive as a last resort (without connecting your Time Machine drive), since you will have to reinstall all your third party applications, and that could take some time, depending on how many your have.