Why is only half my RAM registering?

[LarryF]

I have a Blaster PC running a PIII 600.
I put in a 256 memory stick and it only shows as 128. I tried different slots same thing.
I thought maybe the memory was bad so I tried a good stick of Crucial; same thing.

Do I have a bad M003 motherboard? Anything else I should try?

The machine crashes at times, don't know if this is the cause.

Thanks

 

[pay]

Did you tr re-seating the ram?

 

[Peter]

Well maybe the board's chipset and/or BIOS can't handle that DIMM size. What's the chipset, and are these DIMMs single or double sided?

 

[gaidin123]

It could also be that you bought cheap high density RAM that your chipset doesn't support. If it's only recognizing exactly half of the DIMM size that'd be my guess...

Gaidin

 

[LarryF]

Chipset is 440BX

tried reseating the RAM - not the problem

Tried two different sticks - Kindgston Value Ram and Crucial - same results. The Crucial stick is not cheap

RAMs are double sided

When I tried both sticks (512) it posted 256 and then returned a memory failure message.

Could this be a BIOS setting that I have wrong?

 

[Peter]

"cheap high density RAM", LOL. High density RAM is high density RAM, and cheap RAM is cheap RAM - however neither of these properties designate whether it works or not.

So, Intel BX. 128 MBytes per DIMM side are the maximum, so double-sided 256-MByte DIMMs (those made from "16x8" 128-MBit chips) will work ... UNLESS the BIOS is old enough to be unaware of that chip size.

regards, Peter

 

[LarryF]

OK, Here is the Crucial memory specs:

Module Details:
Part Number: CT32M72S4R7E
? Module Size: 256MB
? Package: 168-pin DIMM
? Feature: SDRAM, PC133
? Configuration: 32Meg x 72
? DIMM Type: Registered
? Error Checking: ECC
? Speed: 7.5ns
? Voltage: 3.3V
? SDRAM Timings:CL=2


The BIOS is Award dated 2/02/01

Thanks

 

[Durron]

Very few BX chipset based boards will handle 256MB dimms.

 

[cnwk64]

all bx board should able to take the 256MB double side memory.
BX can handle up to 1GB memory, 256MB per slot,
I am not sure about the Registered Memory,
If I remember it correctly, standard mobo won't able to support the Registered memory.
that could be the problem.

 

[DJOMCSE2000]

I had the same problem that you're having when I bought RAM for my KT7-RAID boards. The solution? Low-density RAM. It's out there, it's available, and it's not expensive. I would also have to believe that the board will support 256Mb RAM chips. If the board is new enough to support a PIII 600 CPU, it should also support 256MB ram sticks.

Good luck!!

David

 

[Peter]

No room for belief. BX does not support 256-MBit SDRAM chips, it ends at 128.

The rules for registered DIMMs are quite different, and by far not all BIOSes handle them right. Use standard unbuffered.

regards, Peter

 

[Peter]

No room for belief. BX does not support 256-MBit SDRAM chips, it ends at 128.

The rules for registered DIMMs are quite different, and by far not all BIOSes handle them right. Use standard unbuffered.

regards, Peter

 

[LarryF]

Thanks for the responses. Well that kind of sucks.

Any reason not to use my current RAM at only half capacity, So I don't have to buy new?

What does "registered" mean anyway?

 

[cnwk64]

NO, BX board do not support 256-MBit SDRAM chips which will have only 8 chips per stick on a 256MB SDRAM.
However, you can get 256MB SDRAM Stick with 128-Mbit chips on top. those memory have 16 chips total (ecc 18 chips) 8 chips per side.

 

[Peter]

... that's what I said further up this thread, didn't I?

 

[Ramses]

I've had various problems with ram in intel boards over the years, my conclusion is that there are no dead set rules. I've seen LX boards run with more then 512, which they arent suposed to, bx boards run a gig of NON regestered ram, refuse to run with all sorts of configurations that should work, it's crazy. It all depends alot on the board manufacturer/bios as near as I can tell. Trade your stick of 256 on the forums for a pair of 128's...