Mixed DIMMs on P2B-S

[airdale]

I have an Asus P2B-S, v.1.03, with 256mB RAM (2-PC100 128s), Seagate Barracuda, etc. I am running WinME, and everything is working okay.

With the low price on memory, I bought a PC100 256mB DIMM. Problem is that when I installed it, the machine works fine in DOS, but would not boot to Windows. It ALMOST makes it in, but locks up before it gets into WinME.

I removed the 256 and everything was fine. I tried different combinations of slots for the DIMMs, but it would not boot.

Now I am wondering if I should exchange this 256 for 2-128s, or would the machine work if I got a second 256 and had one bank of 2-128s and one bank of 2-256s.

I imagine this is a pretty basic question, but if I knew the answers I would not be asking.

Thanks.

 

[AndyHui]

It's a very high probability that your new piece of RAM does not work....

The BX chipset will only support 128mbit chips....your 256MB DIMM may be using 256mbit chips or 32 x 4 128mbit chips. DIMMs using these chips will not work with the BX chipset.

Try to get 2 x 128MB DIMMs instead....they should work, or ask for 16 x 8 chips on your 256MB DIMMs.

 

[airdale]

Andy -

Thanks for the reply; Dalco is replacing the 256 with two 128s; however, this raises an interesting question.

There are four DIMM slots on my v.1.03 Asus P2B-S. If, as you say, the BX440 chipset can only handle 128mB RAM, then how does Asus claim this board can take 1gB of RAM? To do that it would have to take 256mB DIMMs.

Or can it take the 256mB if they are not mixed with the 128s?Text

 

[AndyHui]

Have a look at my post carefully....I have differentiated between Mb and MB. This is not carelessness on my part.

What I am referring to is 128 megabit chips making up the DIMM of 128 megbytes or 256 megabytes of RAM.

There are two types of 128 megabit chips (each individual chip on the DIMM) available. One is a 16M x 8, the other is a 32M x 4. The BX chipset cannot handle the 32M x 4 type of chip, nor will it handle 256 megabit chips.

There will be 8 x 128Mb chips on a stick of 128MB of RAM; there will be 4 x 256Mb chips on a stick of 128MB of RAM.

It is possible to use 256MB DIMMs, as long as they use 128Mb chips. These DIMMs need to be 16 chips of 16M x 8. There will be 8 chips of RAM on both sides of the DIMM.