Questions about DDR RAM

On Wed, 03 Oct 2007 16:30:41 -0000, Andrew
wrote:


Memory is fairly reliable provided you aren't recklessly overclocking
things so I'd consider ECC inappropriate on all but the most mission-
critical systems. Unless you are talking about a machine already
fitted out with a UPS, hot-swappable RAID, redundant power supplies
and preferably an secure, climate controlled machine room to put it
all in there are more important risk factors to consider.


None of those risk factors change whether the results of
data calculations are important.

I would say ECC is appropriate for any even slightly
critical application, not just "the most mission critical".
You spend a few bucks more for better PSU, case, processor,
etc, why not the memory? Your data links usually have error
correction, as does a hard drive internally, as does the
processor cache, but main memory is a weak link in data
integrity.

Igor wrote:
On Wed, 03 Oct 2007 11:44:59 -0400, class_a wrote:

Igor wrote:

Bottom line: I phrase my questions however I want to phrase them, I
provide whatever information I feel like providing, and if you don't
like it, you can move to the next thread.

With an attitude like that I've a feeling you'll be getting a lot less
answers to your questions in the future!

Out of the dozen or so people who posted useful responses to my
questions, only two seemed to have a problem with how I asked them. Out
of those two, only one tried to make a federal case out of it. And
you're the only person who's felt a need to offer me a civics lesson.

I'm not losing any sleep over the prospect of a couple of sanctimonious
control freaks with delusions of grandeur putting me in their killfiles.
In fact, they'd be doing me a favor if they did; the fewer such people
that I need to deal with, the happier I'll be!

Some people just never learn....

Somewhere on the interweb "Igor" typed:
On Wed, 03 Oct 2007 11:44:59 -0400, class_a
wrote:
Igor wrote:

Bottom line: I phrase my questions however I want to phrase them,
I provide whatever information I feel like providing, and if you
don't like it, you can move to the next thread.

With an attitude like that I've a feeling you'll be getting a lot
less answers to your questions in the future!

Out of the dozen or so people who posted useful responses to my
questions, only two seemed to have a problem with how I asked them.
Out of those two, only one tried to make a federal case out of it.
And you're the only person who's felt a need to offer me a civics
lesson.
I'm not losing any sleep over the prospect of a couple of
sanctimonious control freaks with delusions of grandeur putting me in
their killfiles. In fact, they'd be doing me a favor if they did; the
fewer such people that I need to deal with, the happier I'll be!

Believe me ****er, there's a lot of silent lurkers (one less silent now) who
are absolutely convinced you're a dickhead.
--
TTFN

Shaun.

On Thu, 04 Oct 2007 06:32:17 -0400, ~misfit~
wrote:

Somewhere on the interweb "Igor" typed:
On Wed, 03 Oct 2007 11:44:59 -0400, class_a
wrote:
Igor wrote:

Bottom line: I phrase my questions however I want to phrase them,
I provide whatever information I feel like providing, and if you
don't like it, you can move to the next thread.

With an attitude like that I've a feeling you'll be getting a lot
less answers to your questions in the future!

Out of the dozen or so people who posted useful responses to my
questions, only two seemed to have a problem with how I asked them.
Out of those two, only one tried to make a federal case out of it.
And you're the only person who's felt a need to offer me a civics
lesson.
I'm not losing any sleep over the prospect of a couple of
sanctimonious control freaks with delusions of grandeur putting me in
their killfiles. In fact, they'd be doing me a favor if they did; the
fewer such people that I need to deal with, the happier I'll be!

Believe me ****er, there's a lot of silent lurkers (one less silent now)
who
are absolutely convinced you're a dickhead.

So that makes a whole army of... three in total? Ouch, it sure hurts being
rejected by three anonymous windbags on a usenet forum.

On Wed, 03 Oct 2007 23:05:14 -0400, class_a wrote:

Igor wrote:
On Wed, 03 Oct 2007 11:44:59 -0400, class_a wrote:

Igor wrote:

Bottom line: I phrase my questions however I want to phrase them, I
provide whatever information I feel like providing, and if you don't
like it, you can move to the next thread.

With an attitude like that I've a feeling you'll be getting a lot less
answers to your questions in the future!

Out of the dozen or so people who posted useful responses to my
questions, only two seemed to have a problem with how I asked them. Out
of those two, only one tried to make a federal case out of it. And
you're the only person who's felt a need to offer me a civics lesson.

I'm not losing any sleep over the prospect of a couple of sanctimonious
control freaks with delusions of grandeur putting me in their killfiles.
In fact, they'd be doing me a favor if they did; the fewer such people
that I need to deal with, the happier I'll be!

Some people just never learn....

On second thought, you're going into *my* killfile. You bore the hell out
me.

On Wed, 03 Oct 2007 15:51:56 -0400, kony wrote:

snip



I thought that Newegg started shipping to Canada a couple
years ago. snip

Nothing I've seen on their website indicates that they do. You can't even
type in a Canadian address since you can only enter a ZIP code, no postal
codes. Even if they did ship to Canada, I wouldn't deal with a company
that puts so little effort into attracting Canadian customers (if the
service leaves something to be desired BEFORE you place an order, I don't
imagine it'll improve after an order's been placed).

I'm not sure these types of businesses could ship most parts to Canada
even if they wanted to, as I assume Canada has different standards and
regulatory bodies than the U.S. Also, some parts probably wouldn't be
under warranty in Canada.

Igor wrote:
I'm planning to add some memory to a PC. The motherboard supports "DDR
up to 333 MHz (enhanced) memory bus."

333 MHz (PC2700) or slower DDR SDRAM isn't easy to find on today's
market, and when you do find it, it's considerably more expensive than
the DDR which runs at 400 MHz (PC3200). What would happen if I bought
400 MHz DDR RAM and installed it in a motherboard which only supports
speeds up to 333 MHz (PC2700)? Would it work? If it did work, would it
work as well as the slower PC2700 RAM?

I've gotten conflicting answers to this question. Two computer stores
told me that it wouldn't work. Another store and a book I consulted said
it would.

I'll bet the boys in the first two shops were confused between DDR vs.
DDR2 DRAM. The type of memory you're getting is just DDR memory, and
therefore any memory that conforms to the DDR standard will work on your
mobo. Even slower ones, but they'll just run slower on your system, of
course.

Currently, the most popular type of memory is DDR2, so the older DDR
memories are being phased out, and likely the only stock that is left is
the fastest versions of DDR. So that's why you can't find DDR-333/PC2700
memory anymore, because now they only stock the fastest DDR-400/PC3200
memories. On the other hand, if you were interested in DDR2 memory, then
you'll have all kinds of choices such as DDR2-533/PC4200,
DDR2-667/PC5200, or DDR2-800/PC6400.

I'd also like some opinions on which brand of RAM I should get. Kingston
and Samsung are ubiquitous where I live, so the choice comes down to one
of those. Both brands are about the same price, with the Samsung being
marginally cheaper.

Brand-name doesn't matter, just make sure you buy two of exactly the
same brand at the exact same time, if you're going to be matching it up
for dual-channel operation, otherwise that'll show up as single-channel.

Dual-channel vs. single-channel is another way of increasing the speed
of Dram, with dual-channel being faster than single-channel, obviously.

Finally, would a 128 MB stick of 266 MHz DDR RAM be able to run in the
same computer as, say, a 512 MB stick of 400 MHz DDR RAM? If so, would
using both at the same time degrade the performance of the faster RAM?

Yes, the faster RAM would be slowed down to the speed of the slower RAM.
So it's best to completely remove the old RAM, if you want to gain the
performance advantage of the newer RAM.

As for mail-ordering within Canada, try this site:

www.pricegrabber.ca

Personally, I prefer to do my business with bricks'n'mortar stores
rather than online.

Yousuf Khan

On 2007-10-03 kony wrote:
On Wed, 03 Oct 2007 16:30:41 -0000, Andrew
wrote:

Memory is fairly reliable provided you aren't recklessly overclocking
things so I'd consider ECC inappropriate on all but the most mission-
critical systems. Unless you are talking about a machine already
fitted out with a UPS, hot-swappable RAID, redundant power supplies
and preferably an secure, climate controlled machine room to put it
all in there are more important risk factors to consider.

None of those risk factors change whether the results of
data calculations are important.

I would say ECC is appropriate for any even slightly
critical application, not just "the most mission critical".
You spend a few bucks more for better PSU, case, processor,
etc, why not the memory? Your data links usually have error
correction, as does a hard drive internally, as does the
processor cache, but main memory is a weak link in data
integrity.

Well, some of these factors _can_ affect calculations in the same
manner as bad memory - e.g. anything can happen with a brief power
outage that a regular PSU can _just_about_ bridge, including
incorrect calculations in the CPU, bad data on the bus lines or
whatever. However, I'm not questioning the fact that ECC is
extremely useful and yes, and aid to reliability. What I am
questioning is whether it should be regarded as a priority.

How often do you see bad hard drives, or blown PSUs, or have a
machine cut out in a power cut? These are a computer's weak points
so it makes sense to protect them. It's a little more difficult
to diagnose memory errors in a non-ECC PC because they would usually
appear to be much-more-likely software problems.

However, look at a machine equipped with ECC memory. How often do
you see memory errors logged? Approximately never. Cast your mind
back ten or twelve years when even commodity machines had parity
memory. How often did you see the BIOS message saying it had frozen
the system because of a parity error? I only ever saw it once.
While my memory is vague ISTR that I discounted it at the time as
it was from a system with other hardware problems. Ask yourself
why parity was removed from memory. Yes, it did save money but
why did the computer industry en masse decide that it could safely
be dispensed with?

In short ECC will improve a system's reliability, but not by much.
You are far better off spending the money elsewhere, looking at
more likely causes of failiure, and considering backup, redundancy
etc first. Only when those have been covered is it worth worrying
over whether your machine has ECC memory or not.

--
Andrew Smallshaw

Igor wrote:
On Wed, 03 Oct 2007 23:05:14 -0400, class_a wrote:

Igor wrote:
On Wed, 03 Oct 2007 11:44:59 -0400, class_a wrote:

Igor wrote:

Bottom line: I phrase my questions however I want to phrase them, I
provide whatever information I feel like providing, and if you don't
like it, you can move to the next thread.

With an attitude like that I've a feeling you'll be getting a lot less
answers to your questions in the future!

Out of the dozen or so people who posted useful responses to my
questions, only two seemed to have a problem with how I asked them. Out
of those two, only one tried to make a federal case out of it. And
you're the only person who's felt a need to offer me a civics lesson.

I'm not losing any sleep over the prospect of a couple of sanctimonious
control freaks with delusions of grandeur putting me in their killfiles.
In fact, they'd be doing me a favor if they did; the fewer such people
that I need to deal with, the happier I'll be!

Some people just never learn....

On second thought, you're going into *my* killfile. You bore the hell
out me.

Why thank you, I wouldn't want someone with your attitude possibly
learning something from a post I might make here.

On Fri, 5 Oct 2007 15:17:57 +0000 (UTC), Andrew Smallshaw
wrote:

Yes, it did save money but
why did the computer industry en masse decide that it could safely
be dispensed with?


Because they don't particularly care if a customer's
calculations/etc end up wrong if it's not guaranteed for
some critical use. The industry didn't actually abandon it
for critical uses.