looking for memory

about the meaning of low density??? My understanding is that the term refers to the individual DIMMs NOT the memory circuit card.

Why else would the High Density be the newer type? My understanding is that "high density" refers to the fact that far more MB of memory is on a single DIMM.

It has been normal for many years to pack more and more memory into smaller spaces.

It is true that having higher density DIMMs can result in using fewer DIMMs on a memory stick for a given amount of memory.

Granted, you COULD refer to the micro-components inside an individual chip as being some level of density. That is a memory chip with a 128 million bits of memory is less dense than one with 512 bits of memory. Or you could refer to the density, or chip population on the surface of the board denoting the density, where fewer chips is less dense than one with more chips. And to get to the same amount of memory capacity on one memory board (a SIMM, or DIMM, etc.) with high-density individual chips creates a low density board, or vice-versa.

But jbndhs mentions a spec for a board of ''low density'' memory. That is a selling point. Companies would not normally mention less-desirable features in their literature. You don't see company's mention in their specs things like: old style or slower or ugly. My point being that since the spec mentions it is ''low density'' that is not going to be a bad thing, but they are mentioning a good thing, and the good thing is that there are a low amount of chips on the board - meaning less power consumption.

If you read through bob b's pointed to link, you will see that the person there mentions that boards with more chips is considered ''high density'' and is usually the old style and thus cheaper. Even though bob b seems to think that the article says ''that the number of chips on the module does not have much to do with high/low density.'' In fact, the pointed to article does specify the difference exactly.

That same article does also mention just what I said before, and that is if you can find memory that matches your spec-ed needs (pin out, voltage, speed, etc.) for the price you want to pay, buy it. Forget about the term ''density'' unless you must have the latest and greatest. (and high-density chips make for low density, low chip count, memory boards).

Given the same specs for different types of boards, and for the same or nearly the same cost, I would go with the low density boards because they usually use less power.

My understanding was ... higher density meant DIMMs with the same amount of memory with fewer RAM chips. So in one case you have a 128MB DIMM with 4-32MB chips vs 8-16MB chips. And it usually adversely affected older systems designed to work with low density chips when the mfgs start producing higher density chips and they either don't work at all or erractically.

As another poster has already pointed out.
For example:
"The 256 MB low density module will have 16 chips and the high density module will have 8 chips. The 128 MB low density module will have 8 chips and the high density module will have 4 chips"

It requires more, usually twice as many, chips on a low density module to achieve the same MB count as the high density module.

So, low density is not a good thing, it's not particularly bad either, just much older technology. If you machine can only handle low density modules then that is what you should use. A lot of older machines cannot handle high density modules because of the way that the memory on these modules must be addressed.

If you are ever in any doubt about what sort of memory your machine needs, check out Crucial.com or Ramjet.com and use their configuration tables.

These folks seem to feel that the number of chips on the module does not have much to do with high/low density.

http://www.techsupportforum.com/motherboards-bios-cpu/75262-high-density-memory-low-density.html

Thanks Guys!!!

RE Messages disappearing ...I've had the same thing happen lately.

RE: "No, don't worry about 'low density' that is a good thing. Low density only means it has fewer chips on the whole board to do the exact same thing. And fewer chips generally (not always) means less power needed."

What is your source for this information ? My understanding has always been just the opposite. As mfgs developed higher density RAM chips which could ultimately increase the MBs of RAM on a SIMM or DIMM, they also put some of those high density RAM chips on SIMMs or DIMMs but fewer of them for the desired total RAM. Only problem was the higher density chips just didn't work on a lot of older MBs. Unfortunately lots of advertisers weren't specific enough about their RAM products and neither were the MB mfgs about the RAM types for their MBs. Needles to say...many were disappointed to find their purchases didn't work because of chip density issues. I recently saw a posting by an indivitual with that exact problem on high density 1GB DIMMs...it just didn't work on his MB.

Would love to learn more if there's an authoritative source we can look to.

or part of it. The newer high density DIMM's have two full banks [64 bits] of memory. This is why a 1 MB stick of the newer high density memory may only show 512 MB [as stated in a link provided by another in this thread] on an older mobo. The old mobo bus system only can address one bank. .

I do not know the reason, but I am suspecting that it MAY be related to putting Dual Channel on Athlon XP mobos. I always wonder how they supported Dual Channel yet only had three memory slots. Again, not sure, but I think that with the high density memory sticks having two complete banks, they could actually have each bank connected to a separate 64 bit memory bus, which Intel did using pairs of memory sticks.

Still researching this to be sure.