Difference between parity and ecc?

[jasonlee123]

I know parity is older technology and its crap, but if they both check for errors, then what is the difference?

 

[Mday]

parity has an extra bit for every byte. so each chip has an amount of bits divisible by 9, as opposed to 8.

ecc modules have a "9th" chip as opposed to an extra bit.

--

parity is capable of catching single bit errors.

ecc is capable of FIXING single bit errors, and reporting multibit errors.

 

[Superwormy]

Parity just checks for errors and finds them - 1 extra bit
ECC attempts to repair the errors as well - 8 extra bits

Something like that...

 

[Saltin]

Yeah, parity uses a checksum to make sure the data in memory is not corrupted, if it is it cannot fix it. ECC employs a RAID 5 like philosiphy. Even if there is a certain level of corruption, it is possible to fix it