iMac Memory Upgrade

[nkonstas]

Hi,

Today I've upgraded the memory on my Mac from 4GB (2x2GB) to 8GB (2x4GB - link)

I noticed that after about 20 mins of usage the disk I/O appear to get very slow. Admittedly this is only a guess on my part - but here's what I notice:

- Applications that are already loaded respond fast - for example a page loaded on firefox scrolls smoothly - no perceived slowdown).

- Anything that needs to do any kind of disk access is painfully slow - for example XCode appears to compile files about 5-10 times slower than normal.

- CPU utilization for running applications is too high - for all of them

- A VMWare Windows instance I run grounds to a halt

- If I restart the machine it works fine for about 20mis and then the problems start again

I've no idea why the memory upgrade would cause anything like that.
Btw, I run Lion. If you need any kind of diagnostics dump just let me know.

Any ideas? Should I reset/clear/delete anything following a memory upgrade?

Cheers,
Nikos.

 

[killerrobot]

It's generally recommended to reset the PRAM after a RAM upgrade.
http://support.apple.com/kb/ht1379

Hopefully something simple like that fixes it.
If not try running a RAM test and see if the sticks are good.
http://guides.macrumors.com/Testing_RAM

BTW what iMac are you using?

 

[nkonstas]

According to MacTracker:

iMac 24-inch early 2008 model.
Model identifier: iMac8,1

I will try resetting the PRAM now.

Cheers,
Nikos.

 

[nkonstas]

After reading this I downgraded the memory to 6GB and all seems to good now. Apparently the m/b doesn't support 8GB

Cheers,
Nikos.

 

[malias4]

Glad to hear everything worked out well
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