128mb in a single stick -v- 32 mb in a bank of four

[Croozin]

I was helping a friend update her computer recently, increasing the RAM as she was using some high demand graphics programs. We ended up with a single stick of 128mb RAM left over (wasn't compatible with the newer RAM we put into her computer).

Her husband uses a very clunky P2, which had 32mb of RAM in four banks of 8mb. Thinking I was making the best use of what was available, I removed the four 8mb RAM sticks and replaced them with the single 128mb stick.

A friend has now told him that the 128 mb, because it is in a single stick, is actually slower than the 32 mb in a bank of four sticks.

Is this so?

[Mac the Knife]

D'ye know, if my son ever asks me for some words of advice for life I sometimes think that one of the better ones would be:

"Don't mess with other people's computers" [particularly if they're working more or less OK]

However badly they're set up, no matter what a mess the filesystem is in, no matter how badly fragmented the drive is or how many orphaned clusters there are - LEAVE IT ALONE! They won't care about the speed increase because they've been quite happy with it going kachunck-kachunk for years, something subsequently won't work or they won't be able to find the humongous spreadsheet that has been living one their desktop since Windows 386....

Be pleasant, nod positively and change the topic to flying (you don't know anything about computers..)

[Also keep away from women with migraines, mothers, back problems and those who are too pretty]

And the answer to your question is - maybe! Depends on several things but probably won't make a big difference on a PII.

[Naples Air Center, Inc.]

Croozin,

It does come down to the OS they are using and what they do with the computer.

But as a general rule the computer if the hard drive light comes on every time they try to do something with the computer, then adding RAM will help speed up the computer. (But that only works to a point. There is such a thing as too much RAM that starts slowing the computer down again.)

Take Care,

Richard

[Mac the Knife]

As I tried to avoid explaining in my slightly facetious previous post your chums chum is actually correct in a sort of way.

See http://www.arstechnica.com/paedia/r/ram_guide/ram_guide.part3-1.html

"On an added note, this discussion illustrates why two, 512MB DIMMs of SDRAM will outperform a single, 1GB DIMM. Since each DIMM can have up to four banks, regardless of its size, spreading your memory out among multiple DIMMs offers better performance because of the increased number of banks."

Presumably this is what he may have heard. Just remember that there is NO guarantee that 4x32MB will be faster than 1x128MB - it depends also upon the memory architecture of the mobo and how the designers have chosen to implement this (as well as the RAM speeds and quite a bit of other stuff).

If ya realy really want to get involved in RAS, CAS, tRAC. tCAC, cycle times, dualocts and all the rest of it then Jon "Hannibal" Stokes has an excellent and readable (but necessarily long) tutorial starting at http://www.arstechnica.com/paedia/r/ram_guide/ram_guide.part1-2.html

If you slog carefully through it all and make notes then you'll know more than I do :ok:

[Mac the Knife]

Kay..we're talking about memory interleave here.

Google for: memory + interleave

Lots of stuff. Most relevant is the page at http://www.2cpu.com/Hardware/mem_interleave/

The short answer is that IF your mobo AND your memory will support memory interleave AND you can enable it you MAY gain a bit of speed from this. Probably not worth the farting around unless your're a dedicated hacker.

You'll have to research the rest yourself. Interesting :ok:

[Saab Dastard]

For a given amount of memory, interleaving may offer slight performance enhancement over single stick, as has been highlighted.

However, in almost every real-world situation, an increase in the amount of RAM (4-fold in this case) will improve overall system performance by reducing the amount of paging from RAM to disk.

Not all OSs can make use of large amounts of RAM - particularly 16-bit OSs like Windows 9x, so there isn't much point in throwing RAM at them. Better to upgrade to a proper OS like Linux (but let's not go there!)

SD