iMac crashing, unstable

[pknz]

Another unstable thread.
Running a Rev B iMac 20" 1.5GB RAM (which works fine), 250GB. Mac OS X 10.4.3

Yesterday I installed Poser 6 and the updates, after I installed this I restarted, repaired permissions and restarted again. I then opened Poser 6 only for OS X to lock up (nothing else was running, couldn't force quit). So I held the power button down an it turned itself off. I then powered back up only for the fans to switch into overdrive on the gray screen with the apple logo at startup. The startup did not finish, so again I switched off, started up again with the same result except this time getting to the blue screen with the circle still spinning. I restarted again only to have it get stuck again with the fans going.

On the fourth restart it worked, albeit a bit slower than usual. I ran the daily, weekly and monthly Unix maintenance scripts from Macaroni and repaired permissions. I also ran the Apple Hardware Test which everything passed and then rapaired the disc and permissions from the OS X install disc.

After this I ran Poser 6 again and it worked for about 15-20mins again before locking up the system, before freezing. I held down the power button again and this time it started up (fans going crazy).

Prior to this I have had issues with Safari, iTunes and the weather widget unexpectedly quitting. I had also defragmented using the latest Drive Genius. The iMac feels slower then it did at start up and launching Safari before all this happened?

Do you recommend I wipe the drive and reinstall the OS, are there better solutions?

Any help would be great.

EDIT: After the first series of crashes I noticed a folder inside the harddrive called
lost+found
inside this folder is another folder called 2995712 inside that folder is
configd.pid, diskarbitrationd.pid, lookupd.pid, memberd.pid

 

[pknz]

Since then I have run Diskwarrior and am in the process of running TechTool but neither have come up with any problems.

 

[mad jew]

RAM can pass all tests but still be bad so maybe take out the extra chip and see how things go.

Having said that, you imply that it's more likely to have something to do with Poser 6 (maybe the updates although apps were slow beforehand) so do all the usual maintenance tasks, restart and see if the problem pops up. Do not run Poser in the meantime. I personally think it's more likely to be the RAM though.

Good luck with it all.

 

[pknz]

I don't think its the RAM as the machines worked well for the past half year or so. But I will look into it, thanks for the advice

 

[mad jew]

Sometimes RAM goes bad because of a trigger event (like the Poser install or updates). What was the RAM being used in before the iMac? Was it a PC? iMacs are notoriously picky with RAM.

Good luck with it all.

 

[pknz]

The RAM was bought (new) with the iMac (although might not be Apple RAM).