What difference between EDO DRAM and EDO parity RAM?

What difference between EDO DRAM and EDO parity RAM?

Post by Geena Pa » Wed, 27 Nov 1996 04:00:00



  Hi, subject says it all. Could anyone explain difference between
  EDO DRAM and EDO parity RAM?  I need to know about it to decide
  between Gateway 2000 and Dell. Forgive me if this is too ignorant
  a question, but I am not much of a hardware buff...
  Thank you in advance.
--
  _____________
  M. Geena Park

 
 
 

What difference between EDO DRAM and EDO parity RAM?

Post by bill davids » Tue, 10 Dec 1996 04:00:00



|   Hi, subject says it all. Could anyone explain difference between
|   EDO DRAM and EDO parity RAM?  I need to know about it to decide
|   between Gateway 2000 and Dell. Forgive me if this is too ignorant
|   a question, but I am not much of a hardware buff...
|   Thank you in advance.

Parity RAM of any type allows you to detect memory errors (parity)
or to correct single bit memory errors (ECC) if your chipset
supports this. The Intel 430FX (aka Triton I) does not, the HX does
and the VX spec say it does (but I don't have one).

I use parity memory on all systems, on the basis that I have no game
playing machine, and any other use suggests having correct answers
is desirable. I would rather have my machines down than get answers
I can't trust.

About Partity/ECC:

Q: Does parity slow down my machine?
A: No, it's done in hardware. Some machine have a debug mode for
   locating errors, which may be slower, but normal detection doesn't
   effect the speed.

Q: Does ECC slow down my machine?
A: Maybe. On some chips set with some access patterns. I've never
   been able to detect the slowdown, but it's possible in theory to
   lose 1-2% in write time if memory is heavily used. this is usually
   not the case with a single processor.

Q: will parity or ECC make my machine more reliable?
A: ECC will be able to correct some errors, so the machine may be
   more reliable. Parity make the machine less reliable (an error in
   a parity bit can report an error when the data is okay, but the
   results are more reliable, because there have been no single bit
   errors.