ECC Vs. Non-ECC RAM

[Pack Fan]

Is the added speed and lower price of non-ECC a big enough factor to decide
for a particular MB? Will I even notice a difference in speed of ECC vs.
non-ECC RAM? (I'll be buying four 512MB DDR PC2100).

That's the main question. The rest of this post is just further info.

I'm comparing two MBs. The SUPER X5DAE
(http://www.supermicro.com/PRODUCT/MotherBoards/E7505/X5DAE.htm) and the
SUPER X5DAL-TG2
(http://www.supermicro.com/PRODUCT/MotherBoards/E7505/X5DAL-TG2.htm).

As I see it the differences between the two of each are as follows:

X5DAE
12GB max RAM (but it must be ECC),
PCI expansion slots:
1 64-bit 133MHz PCI-X
2 64-bit 100MHz PCI-X
2 32-bit 33MHz PCI
AC'97 audio CODEC high quality 6-channel sound

X5DAL-TG2
8 GB max RAM (but it can be non-ECC)
4-port Serial ATA ( RAID 0, 1)
PCI expansion slots:
1 64-bit 133MHz PCI-X
1 64-bit 66MHz PCI
2 32-bit 33MHz PCI
(i.e. fewer and slower than the X5DAE)
no onboard audio

So the question is do I go for the slightly less expensive ($40) X5DAE and
pay more for slower RAM or do I go for the X5DAL-TG2 with cheaper faster
RAM?

Thanks much,

Dave

 

[Bill Woessner]

Is the added speed and lower price of non-ECC a big enough factor to decide

for a particular MB? Will I even notice a difference in speed of ECC vs.
non-ECC RAM? (I'll be buying four 512MB DDR PC2100).

If I were you, I would ask myself whether or not I NEED ECC RAM. If
you're building a mission critical machine, then you absolutely have to go
with ECC RAM. If it's just for home use... that's another story. If you
take personal offense at your computer crashing, you might want to invest
in ECC RAM.

--Bill

 

[Pack Fan]

If I were you, I would ask myself whether or not I NEED ECC RAM. If
you're building a mission critical machine, then you absolutely have to go
with ECC RAM. If it's just for home use... that's another story. If you
take personal offense at your computer crashing, you might want to invest
in ECC RAM.

--Bill

Good question. Is non-ECC RAM really so suspect that one has to worry about
it crashing one's machine? OTOH, is ECC so slow as to warrant using it only
in mission critical applications?

Frankly, I do take crashes personally. I'm hoping that Win 2K server is
going to provide a much more stable machine than Win 98SE.

But what I really want to know is how much speed am I going to sacrifice
using ECC instead of non-ECC RAM.

Thanks,

Dave

 

[jeffc]

Is the added speed and lower price of non-ECC a big enough factor to decide
for a particular MB? Will I even notice a difference in speed of ECC vs.
non-ECC RAM?

It's not about speed, it's about data correction. Most home users don't
need it. Probably a case of "if ya gotta ask, you don't need it."

 

[Bob Day]

Is the added speed and lower price of non-ECC a big enough factor to decide
for a particular MB? Will I even notice a difference in speed of ECC vs.
non-ECC RAM? (I'll be buying four 512MB DDR PC2100).

See "ECC Memory Isn't Everything -- It's the Only Thing" under
"Programming" at http://bobday.vze.com

-- Bob Day

 

[Pack Fan]

See "ECC Memory Isn't Everything -- It's the Only Thing" under
"Programming" at http://bobday.vze.com

-- Bob Day

Thanks Bob! This is exactly the information I was seeking.

So, basically, the only significant negative I see from using ECC memory is
price. Unfortunately, it's pretty significant. For the 512 MB DIMMs I've
been looking at ECC is about 50% more expensive.

Dave

 

[jeffc]

But what I really want to know is how much speed am I going to sacrifice
using ECC instead of non-ECC RAM.

Actually, when I posted my first reply, I thought you thought ECC RAM was
faster

 

[Jim Taylor]

Is non-ECC RAM really so suspect that one has to worry about
it crashing one's machine?

No, especially if you buy high quality memory chips. Your computer is
_MUCH_ more likely to crash because of a program bug than from a memory
error. I read an Intel white paper about this years ago and the bottom line
was don't waste your money on ECC (except for mission critical stuff).

 

[Pack Fan]

No, especially if you buy high quality memory chips. Your computer is
_MUCH_ more likely to crash because of a program bug than from a memory
error. I read an Intel white paper about this years ago and the bottom line
was don't waste your money on ECC (except for mission critical stuff).

I would go for the non-ECC but a few other factors are pushing me towards a
MB that requires it. In any event, it appears that the performance factor is
nearly negligible.

Thanks,

Dave

 

[Gary W. Swearingen]

So, basically, the only significant negative I see from using ECC memory is
price. Unfortunately, it's pretty significant. For the 512 MB DIMMs I've
been looking at ECC is about 50% more expensive.

Consider basing your percentage on the cost of the computer (maybe
including the costs of corrupted important data) instead of on the
cost of the RAM.

As for error rates, I found two reports (apparently) from big-system
guys with ECC correction statistics in their logs: One saw 50 per day
in 220 GB (at 1 km altitude). The other saw 1 per week in 37.5 GB
(unstated altitude, likely near zero). That's 83/year/GB and
1.4/year/GB, with altitude being the probable cause for the different,
because cosmic rays are the principle root cause. (Radioactive
contaminants is said to be less of a problem than they used to be.)
One memory maker reports expectations of 8 to 48/year/GB.

I've noticed that modern CPUs use ECC in their internal memories.

 

[Pack Fan]

Consider basing your percentage on the cost of the computer (maybe
including the costs of corrupted important data) instead of on the
cost of the RAM.

As for error rates, I found two reports (apparently) from big-system
guys with ECC correction statistics in their logs: One saw 50 per day
in 220 GB (at 1 km altitude). The other saw 1 per week in 37.5 GB
(unstated altitude, likely near zero). That's 83/year/GB and
1.4/year/GB, with altitude being the probable cause for the different,
because cosmic rays are the principle root cause. (Radioactive
contaminants is said to be less of a problem than they used to be.)
One memory maker reports expectations of 8 to 48/year/GB.

I've noticed that modern CPUs use ECC in their internal memories.

Before I started researching this ECC vs. non-ECC I had no idea that errors
would crop up in non-defective RAM. Of course, since my production machines
are running Win98SE (yes, I know, big mistake) and crash multiple times
daily there's no way I'd've ever noticed a RAM induced crash or corruption.

It's ECC RAM and Win2K for my next machine.

 

[Nick Le Lievre]

memory

Before I started researching this ECC vs. non-ECC I had no idea that errors
would crop up in non-defective RAM. Of course, since my production machines
are running Win98SE (yes, I know, big mistake) and crash multiple times
daily there's no way I'd've ever noticed a RAM induced crash or corruption.

It's ECC RAM and Win2K for my next machine.

Its been a long time since I ran Windows 98 as my main o/s perhaps 3 1/2
years and my computer usage and knowledge esp when it comes to hardware
failures has grown since then but I don`t remember Windows 98 crashing
multiple times daily - I would suggest that the Ram in which errors are
cropping what you describe as non-defective ram is in fact defective. This
post describes defective ram problems (the PCs with these problems were
running XP) http://tinyurl.com/w3t0