a question about RAM

[MarChaosTheory]

what is better, 1 x 256MB simm or 2 x 128MB simm

or more specifically, or average quality 256MB simm or .... 1 good quality 128MB and one average quality 128MB ??

im typically interested in PC133 if there is any difference...


thanks...

 

[Jeff7]

Just a little on terminology. SIMM's are old - 30 or 72-pin usually. PC66/100/133 are DIMM's - SDRAM (synchronous dynamic RAM). SIMM's always needed to be used in pairs, or sometimes in 4's. DIMM's can be used in single.

Anyway, there is no difference in performance between a single 256MB stick, or 2x128MB sticks. As for quality, I think that the total RAM speed is limited to that of the worst stick on the board. (I think that the board uses the same timings for all sticks, but I could be wrong about that. The BIOS setup generally only allows you to tweak settings globally - they affect ALL sticks, not just particular ones.)

 

[Bloodstein]

i always thought 1 ram module is better than 2 ram modules....apparently not!?

 

[Alphazero]

Originally posted by: Bloodstein
i always thought 1 ram module is better than 2 ram modules....apparently not!?

Generally it is better to have one stick rather than two, for reasons of stability and speed.

 

[halkebul]

Sometimes it's good to have two because if one module malfunctions for whatever reason you can still use the system until you solve the problem. For dual memory controller chipsets, nForce and nForce2 for example, always good to have two.

 

[Kingofcomputer]

Single side uses half the number of ram chips than double side, since it's newer and bigger (256Mbit vs 128Mbit or 512Mbit vs 256Mbit, and so on) memory chips .

Many motherboards have 3 slots, but the chipset (such as 845) only supports 4 banks, so if you put in 2 double side, the last slot is useless.

The only drawback of single side is your motherboard chipset could be too old that doesn't support the newer bigger size memory chips, like in the old day BX chipset supports up to 128Mbit chips, so only can use double side 256MByte module, not single side 256MByte module.

 

[Whitedog]

Kingofcomputer,

That's true of some "crappy" Intel chipset mobo's... Any "GOOD" mobo can use any combo of RAM. 😉 This computer has 3 DIMM slots... I have 3 - 16chip 256MB DIMMS in it (768 total) and it works fine.

MarChaosTheory,

To answer your question, the less modules you can use the better off you are. It's kinda like the raid 0 factor. One larger unit is less likely to fail than 2 units... if you follow me.
Also, it's easier on the OS to only have to address a single module than two. I don't think it affects performance as much as it does the likely hood of read/write errors occuring.
In other words, your likelyhood of getting the dreaded memory address error is much lessened using a single module.
When you "mix" memory module up (in other words install an 8 chip brand "x" chip and a 16 chip brand "y" chip) you increase your chances of memory address error a BUNCH! Avoid doing that.

Just a little on terminology. SIMM's are old - 30 or 72-pin usually. PC66/100/133 are DIMM's - SDRAM (synchronous dynamic RAM). SIMM's always needed to be used in pairs, or sometimes in 4's. DIMM's can be used in single

SIMM stands for Single Inline Memory Module.
30 Pin SIMMS are 8 bit
72 Pin are 32 bit.
Older systems, like 486's had 32bit memory bus. You could use a single SIMM in those, or multiples of 4 - 30pin SIMMS to make up the required 32bit address.

The Pentium bus (which we're still on) uses a 64bit bus address, and requred 72pin SIMMS in pairs. (or single 64bit DIMM when the ZX chipset came out)

DIMMS, or "Dual" Inline Memory Modules are nothing more than 32bit chips running in parallel giving you the required 64bit address.

The nForce is made to recognize either a 64bit address (1 or 3 DIMMS) or a 128bit address (2 DIMMS only - running in parallel)

Hope that helps