Can somebody explain the practical differences between ECC and Non-ECC DDR2 RAM for the new PowerMac G5? I know that ECC means "error correction" but what exact errors is it correcting? As far as I know I've always used Non-ECC before and haven't experienced any problems... or might I have and not known it? What exactly is the difference?

Also, I've heard that ECC RAM is slower because of all the "errors" it's correcting. Is this true and if so how much slower is it? I am mostly going to be using my system for video editing (HD) and graphics work.... do I need to invest in ECC RAM?

[Gargoyle]

ECC/Non-ECC Page

And for the really lazy - "Omg I have to click the mouse again!?!?" - here's the short version..

You may have to decide whether you want ECC or non-parity. ECC can find and correct some memory errors, but it comes with a performance price-it will slow your system by about 2%. Fortunately, memory errors are rare in today's memory chips, so most average users don't have a need for ECC ... SNIP ... For most consumers, however, it is not necessary due to the low rate of errors in today's memory, and actually involves a slight performance hit.

My view: If you are running a server or some mathamatica type app that will spend hours crunching data without saving to disc, then get ECC. If your just a power user in Photoshop or whatever, then get normal RAM and keep pressing CMD-S often!

Think of it this way, when was the last time your machine crashed because of a memory error?

Edit:
My webserver is running ECC memory. So far it has not detected any memory errors in the last...

[admin admin]$ uptime  9:34am  up 218 days, 14:22,  1 user,  load average: 0.24, 0.25, 0.23

... 218 days, nice!