Adding more RAM

I thinking about adding more RAM to my comp but had a question about some info I pulled up. I attached an image so you guys would see. Now on the left its telling me that the max of RAM that we can put in each slot is 512MB. Now on the right it says Max Registered DDR SDRAM : 2048 MB (2GB) Can someone explain that and if I can really put 1GB in each slot.  Capture
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it_saigeConnect With a Mentor DeveloperCommented:
Straight from the manufacturers website []:

2 DDR DIMM sockets and 2 DIMM sockets support (can not be used simultaneously)
• Two 184-pin 2.5V DDR SDRAM (DDR266/DDR200) or
• Two 168-pin 3.3V SDRAM (PC133/PC100)
• Maximum: 2GB DDR or SDRAM (Buffered) / 1GB DDR or SDRAM (Unbuffered)

In other words,

You can use 2 1GB 2.5V DDR SDRAM (DDR266/DDR200) for a maximum of 2048MB (2GB)


You can use 2 512MB 3.3V SDRAM (PC133/PC100) for a maximum of 1024MB (1GB)

The results from crucial are correct as the motherboard is reporting what you are allowed to use in your current memory configuration.  By the report you are currently using your 3.3V Slots.  The motherboard has disabled the other slots.  If you decide to use your 2.5V slots, you would see similar results with exception that the memory size and speed allowed would change.


Yes, it looks like the maximim amount of RAM you can have in any given slot is a 512mb stick.  From the looks of it, you have 4 slots, so 4 x 512 is 2048mb (aka the maximum amount of memory that your machine can handle).

Hope this helps!

Go to and run their memory scan tool. This should tell you how much ram you can use and which slot.
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@discgman:  The image he provided is from ;)

System info:

Standard Memory:       0 MB  (Removable)  

Maximum Memory:       2 GB  

Expansion:       2 Sockets   for DDR modules (184-pin)
2 Sockets   for SDRAM modules (168-pin)

CPU & ChipSet:       Intel Pentium 4     VIA Apollo P4X333 (VT8754)

Bus Architecture:       PCI

Mfgr's System P/N's:       N/A

Comments       This board supports both DDR (KVR266X64C25) and SDRAM (KVR133X64C3) memory technologies. However, they cannot be mixed at the same time.

Bank Schema

The following information (Bank Schema) describes the original memory configuration of this device, as well as the sockets available for upgrade. If you have any questions regarding the memory configuration of this device, click here

For SDRAM modules (168-pin):
Oh and if the manufacturers specifications were not clear enough.

You can only use your 2.5V slots or your 3.3V slots, not both at the same time.

I see you have a dilemma.
There are two types of RAM on this board, SD and DDR.
Rules:  You CANNOT mis RAM types, so either you put in  SD or you put in DDR, your choice.
If you opt for SD, then the mas amount is 512Mb, whereas if you opt for DDR the max amount is 2Gb,
So although the instructions are correct, it does not clearly show that the difference is due to the type or RAM you insert.
You can have the floowing configurations:
SDRAM: 256MB in slot 1; 256MB in slot 1 and 2, 512MB in slot 1, 512MB in slots 1 and 2 - giving max of 1GB, since SD can only be up to 512MB each
DDR RAM can be any combination of 256MB, 512MB or 1GB in slot 1 or slot 1 and 2 - giving max of 2GB.

So, really it all depends on the RAM slots you will be using.  I think I am right in assuming that there are actually four slots on that board, two SD and two DDR.

Let me know if this clears the matter up.
1GB modules (either DDR or SDRAM) must be buffered RAM and not the more common unbuffered modules. So, yes, 2GB of either DDR or SDRAM is possible with buffered modules. Since that is an older motherboard, stick with 2 512MB unbuffered modules, preferably DDR.
lupelealAuthor Commented:
Whats the difference btwn buffered and unbuffered?
Although I have copied this from another site, it'll explain it well - I couldn't have done it better:

DDR and SDRAM can be unbuffered or registered. EDO and FPM can be buffered or unbuffered. Buffered modules contain a buffer to help the chipset cope with the large electrical load required when the system has a lot of memory. Registered modules do not have a buffer but do contain a register that delays all information transferred to the module by one clock cycle. Buffered and registered modules are typically used only in servers and other mission-critical systems where it is extremely important that the data is properly handled.


Memory modules 101: The basicsPart Number
This is the unique identifier that Crucial assigns to every memory module.
Module Size
The total number of bytes (usually expressed in megabytes or MB) on the memory module.

The number of pins (30, 72, 100, 144, 168, 200) and the type of memory module (SIMM, SODIMM, DIMM, RIMM) for this part number.

The type of DRAM on this memory module. Current DRAM types includes FPM, EDO, SDRAM, DDR, and RDRAM.

« back

This describes the structure of the memory module. The first number is the depth of the module (or, the number of signals the module sends at one time). The second is the width (of the module's data bus). To get the total megabytes of the module, multiply the depth by the width and divide by 8 (or 9 for ECC or parity; if you're not sure if you have ECC/Parity divide the width by which ever one gives you an integer). For example, a 16M72 is 16 x 72 / 9 = 128MB.
This refers to how the DIMM processes signals. There are three DIMM types: buffered, registered, and unbuffered. Most memory modules are unbuffered.

Buffered modules contain a buffer (usually when there's a lot of memory) to help the chip set cope with the large electrical load required. The buffer electrically isolates the memory from the controller to minimize the load that the chipset sees.

Registered modules contain a register that delays all information transferred to the module by one clock cycle. Again, this is usually done on modules with a lot of memory to help ensure that the data is properly handled.

Most buffered and registered modules also have ECC and are used in servers. FPM and EDO modules are either unbuffered or buffered. SDRAM modules are either unbuffered or registered.

Buffered (also called registered) modules have a buffer (register) chip which serves as the interface between the memory controller and the module. It usually is both ECC and registered and is normally used in servers.
lupelealAuthor Commented:
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