Well 6 months before i had 128 mb of ram on my intel pentium III desktop board with cpu speed 800 Mhz...Then i brought another 128 mb RAM to make it all together 256 mb RAM.
IT WORKED WELL FOR 6 MONTHS......SHOWED 256 MB OF RAM IN BOTH BIOS AND IN WINDOWS
Suddenly after 6 months.....I found my machine pretty slow .....i checked the BIOS there it shows only 128 mb of total memory though there are two 128mb rams on the slot. I removed the old RAM and rebooted the computer it ran ok without any prompts...and again i removed new one and replaced old one on the booting time it prompted me with the following messsage in the console/

SERIAL PRESENCE DETECT (SPD) DEVICE DATA MISSING OR INCONCLUSIVE. PROPERLY PROGRAMMED SPD DATA IS REQUIRED FOR RELIABLE OPERATION.

DO YOU WISH TO ATTEMPT TO BOOT?
Y/N [Y] TYPE [N] TO SHUT DOWN

When i pressed y it continued started booting and i can go to windows desktop....
i changed the slots but similar problem... I have three slots for RAM in my board.

When two RAMs are present it only shows 128 mb of RAM..both in bios and in windows.
What is the problem? what should I do? Please help me out!

I have INTEL 82815 pentium III 800 MHZ Machine

Thanks
sabin

Welcome to the PC Guide Forums!! :D

Hmmm... sounds like your old stick of RAM died. If the new one works fine, but the old stick gives you that error, then just replace the old one. Are any of your old parts still under warranty?

but it well works when I continue with booting?? and my old parts are still working well.

When two RAMs are present it only shows 128 mb of RAM..both in bios and in windows.This suggests a problem with the older stick of RAM since it gives you the error by itself and doesn't show up when both are installed. Have you tried the third RAM slot by any chance?

Download and run MemTest86 (http://www.memtest86.com/) to be certain, but I still think your old stick of RAM is bad.

See:
http://arstechnica.com/ask-ars/2000/ask-08142000.html
http://www.intel.com/support/motherboards/desktop/d810e2cb/sb/cs-012912.htm#14.0
http://www.itanium.org.uk/support/motherboards/desktop/rc440bx/sb/cs-013611.htm

Well I have tried the third slot too but still same problem......earlier both RAM were working together correctly........and that message is not appeared when new RAM is used....
If my old RAM is gone bad Why it is still working? I can do lots of heavy stuffs with this RAM...
These two RAM works one at a time but not together.....
If i use both of ram together IT shows 128mb of ram and the thing that made me surprised that in window it showed the MY CPU SPEED 596 mhz but actually it is 800Mhz

If my old RAM is gone bad Why it is still working?It isn't working. You said so yourself, the system shows only 128MB total when two sticks of 128MB are installed. Ergo, your old stick of RAM (which is producing that error) has gone bad. If you can't use them both together, what's the point of having them both? I say toss the old one and get another new stick of RAM.

Your CPU speed is another issue entirely. Very suspicious. Download and run WCPUID (http://hp.vector.co.jp/authors/VA002374/src/download.html) and tell us what it says. Something is amiss...

and one thing when i insert new RAM it shows Total Memory 128mb
Memory bank 0 128 (PCI33)
But with old one it only shows memory bank 0 128mb only no PCI33........Is really my RAM went off??
in BIOS.

"Is really my RAM went off??"
That's how I see it.
See http://www.pctechguide.com/03memory_Presence_detect.htm
QUOTE
"The Serial Presence Detect function is implemented using an 8-pin serial EEPROM chip. This stores information about the memory module's size, speed, voltage, drive strength, and number of row and column addresses, parameter read by the BIOS during POST."
Looks like your BIOS's POST is unable to retrieve any info about the RAM stick during the POST, so gives that warning.
I wonder if the RAM is working despite that and when you give the go-ahead and boot into Windows with only that stick of RAM does it work ok?
If so, you could decide to use it anyway, or else take no risks and replace it.

It's possible your old RAM is ECC pc-100 Ram and the new one of pc-133 is incompatible with it. But, if you say they were working together earlier and they totalled 256, then I would look into a possible BIOS setting limiting RAM and also as to why your processor is running at the wrong speed.

Here is the attachment. here are two screenshots..one with old ram and another with new ram separately.........and have a look at the differnces in the image. I have used http://www.cupid.org 's cpu-z tool to view RAM information. All the informations are shown same, the different that is shown is in attachment.
Please have a look at screenshots and help me out wat is wrong?
Now

thanks
darkangel

See http://www.pcguide.com/ref/ram/tech_SDRAM.htm
QUOTE
"Serial Presence Detect: Some motherboards are now being created that require the use of special SDRAM modules that include something called a Serial Presence Detect (SPD) chip. This is an EEPROM that contains speed and design information about the module. The motherboard queries the chip for information about the module and makes adjustments to system operation based on what it finds. A great idea in theory, but you won't think it's great if you buy an SDRAM module without the chip on it when your board requires SPD..."

well but initially two ram worked together nicely.....how come this happen suddenly after 6 months? please have a look at the attachment that i have attached before your reply. The attachement contains the information of two RAM separately ,i.e. old and new one. Now this is the information shown when two ram's are combined.

Thanks
darkangel

I did view the images side-by-side and saw the differences, but what does it mean?
The obvious?
That the SPD is unable to detect the information that would fill in the two gaps on timing frequency and ratio.
And why is it unable to do this?
Was the SPD working previously with this stick but not now?
Why not now?
Because the stick has gone faulty?
Has the "Serial Presence Detect (SPD) chip" gone faulty on this stick of RAM?
The "EEPROM that contains speed and design information about the module"?

So it would seem. :(

Then is my old RAM Completely useless now though it works when it is slotted alone without the new one??

Is it useless?
You said:
"Suddenly after 6 months.....I found my machine pretty slow .....i checked the BIOS there it shows only 128 mb of total memory though there are two 128mb rams on the slot."
Then you said:
"but it well works when I continue with booting?"
Then...
"Why it is still working? I can do lots of heavy stuffs with this RAM..."
Then...
"These two RAM works one at a time but not together...."
Then...
"it works when it is slotted alone without the new one"

Not much good if they only work as a single stick, but you want both to work together.
You are there using the PC and are best placed to decide what to do.
Either you settle for using only a single stick, or you replace your old stick with one that matches and works well with the new stick. :)