Few questions about RAM memory?

you need to check with board to fine what ram works with first.i use what they say to use so no problems later and save money as well ok jim

This mainboard uses DDR400 memory

A High Density module is by far much slower than Low Density module at the same speed rating say PC3200/DDR400. High density modules are FAR CHEAPER, less than half the price when compare with low density modules and hence high density modules will NOT work on 90% of today's PC chipsets. LOW DENSITY modules have 100% compatibility with ALL systems and ALL chipsets. HIGH DENSITY modules only have 10% compatibility and are VERY SLOW.

So AVOID those 'High-Density - 128Mx4 config 1GB modules which is usually UNBRANDED and is NO NAME!

With this in mind it is far better to use low density Ram. Most RAM cards today are double sided, it all depends on the capacity of the RAM card.

Please rate this solloution as it it much appreciated.

Thanks.

Not different types per se, but you may be able to put different speeds.

Type would be like DDR Sdram, or DDR2 Sdram for example.

Speed is a slang term for Frequency Rate. What frequency rate does the ram memory module (Stick) operate at.

Example: DDR2 Sdram that has a frequency rate of 667MHz. (PC2-5300) MHz stands for MegaHertz.

Mega = approximately 1 Million. Hertz stands for Cycles per Second.

The above ram memory module operates at 667 Million Cycles per Second.

If you install two ram modules that have a different frequency rate, all the ram memory installed will operate at the slower frequency rate.

(Provided the computer will support more than just one frequency rate)

Have a computer in mind, or is this just a generic question? A what if?


Reply to your recent comment:

If this is in relation to two different manufactures of your ram memory, it shouldn't be a problem.

Where you may get into trouble in this area, is if one ram memory module (Stick) is generic, or low budget, and one ram memory module is a high performance gamer ram memory.

Without knowing the exact manufacturer of your computer, plus the Model name of it, and also knowing the information you have about your ram memory 'sticks', the following information is just generic, or general information.

High performance ram memory may use a higher voltage. Not always, but a good portion of the time.

High performance ram may also use a faster set of ram timings.
It may also have high density DRAM chips, and the chip configuration may be setup differently.

(The black rectangular modules you see on the side of a ram memory 'stick', are DRAM chips)

To explain so far;

SDR Sdram was the typical ram memory for years after SIMM ram memory.
SDR stands for Single Data rate.
Commonly just referred to as Sdram, but in actuality that is erroneous.

(Sdram stands for Synchronous Dynamic Random Access Memory)

Then came DDR Sdram.
Double Data Rate Sdram.
Then DDR2 SDram.
Double Data Rate 2 Sdram.
Then DDR3 Sdram.
Double Data Rate 3 Sdram.

1) http://en.wikipedia.org/wiki/SDRAM

(Anything you see on a Wikipedia page that is in blue, is a link to more information.

To further illustrate this,

2) http://en.wikipedia.org/wiki/DDR_SDRAM )

SDR Sdram specifications were all over the place. What was considered to be a standard for one manufacturer, differed for another manufacturer.

The JEDEC organization was formed.
JEDEC sets the standards for ram memory from DDR Sdram on up.

Voltage for DDR Sdram is 2.5 volts
DDR2 is 1.8 Volts
DDR3 is 1.5 Volts.

Ram manufacturers found that by upping the voltage requirement on high performance ram, the ram could perform, better.
Not true in all cases, as there is high performance ram that operates at the JEDEC standard.

Ram timings were also varied.
Also the chip configuration
Plus the density of the DRAM chip.

Unless it is a really cheap, generic ram module, (Stick), there will be a manufacturers code on the side.
With this code I can tell you the specifications of that ram module.
I can also explain

No, DDR 400 will not work. The best thing you can do is call Dell and give them your information. Model number and that kind of information and let them tell you what kind of ram you need. If you put the wrong type of ram in your machine it could cause major damage. There are so many different kinds of memory out there, not to mention high and low denisity. Your machine may use PC2700 high density and if you try to use PC2700 low density it will not work. One other thing that you can try is uninstall a stick of your ram and write down everything on the stickers and then go to some place like kingston memory and use their memory locator to find what you need.

Look at the sticks of RAM -- "high" density means fewer chips on each side of the stick, i.e., newer technology and production methods have packed more bits into each chip, while "low" density usually means 8 chips/side, using older RAM chips.

Older motherboards do not expect to find "high" density RAM, and typically will only detect 1/4 or 1/2 of the RAM on the stick.

If you buy a new motherboard, it will support BOTH densities.

You need the low density ram and not high density. Unfortunately the low density stuff is rather more expensive then the high density so you're best trying to get some second hand - ebay maybe? I think the cpx only accepts pc100 even though the crucial site recommends PC133. Hope this helps.

Do you have onboard video on this computer? If it has integrated video on the motherboard, the motherboard will be stealing (sharing) a small bit of your MEMORY for it's own use. This is normal with integrated video..
If you have a video card in and expansion slot with it's OWN memory on the card , then it will not use the systems' memory.
I would choose low density for compatibility with the widest range of computers.

The Motherboard limitation are DDR400 = 2GB maximum size per slot
Allthough you can with slower memory DDR333 or DDR266 go to the 3GB memory limit.
Due to the age it will be trail and error on the memory types. You won't necessary get any problems with the high density memory as long as it is good quality memory and you don't exceed the slot memory limit as mentioned above.
I recommend that you download the motherboard manual and read it.

Go to Crucial.com and install their configuration utility through your browser. They will tell you what you have and all the combinations you can do to max out your system. Look at the specs of the RAM and you can get it from Crucial or some other vendor.

Is it a High Density memory? There are two different types of memory, High and Low. Low density is the universal but High density, may be cheaper but the motherboard needs to be compatible with High density memory. Although your memory fits in the slot, I think you have High density memory hence why it won't boot up and does when you remove the memory.