Incorrect memory showing

[bradcom]

Hi there, I'm trying to upgrade the ram on an old Compaq Presario and the system doesn't appear to be giving me the correct value for the ram I put in.
First of all I thought it was wierd that it was showing as only having 16mb originally (PC100), but when I took it out it said 32mb on the stick. I replaced it with a 128mb stick, but the computer is only showing as having 18mb's now.

Any idea's? Help would be appreciated.

 

[kippy13]

Hi,
Firstly does the machine support that much ram?
Have you tried both sticks in another machine and what do they show up as?
Where are you taking the reading of ram, in the BIOS or from the O.S?
What RAM did you originally have in the machine?
Sometimes the OS will not show a full reading of RAM as some of it is being used for shared graphics or shadow BIOS however in this case I feel that it is either bad RAM(unlikely that two sticks are bad), the DIMM slot is damaged, or the machine does not support this type or this much or RAM.(most likely)
You may also need to upgrade the BIOS of the machine although I doubt that this would be causing the issue.

"Sometimes I do not know but I try hard"- R.F. Haughty 1923

 

[spool]

Go to Compaq's web site and see if they have a BIOS update for your model. I had the same problem, updated the BIOS and now has correct reading.

Compaq makes their own mother boards and some times you can only upgrade with their memory.

Spool

 

[cdogg]

Compaq PC's (particularly old ones) are extrememly picky about their memory. Many brands simply won't work with them.

It is best for you to buy from a vendor who will guarantee compatibility or your money back. A good place to check compatibility is at

http://www.crucial.com,

which has a configurator you can use to make sure you're getting the right kind.

Also, don't overlook the fact that older systems tend to work with less amounts of RAM. It would be great if you could provide us with the specs of your Compaq (model, brand of RAM, CPU speed, and/or CPU type).

~cdogg
[tab]"All paid jobs absorb and degrade the mind"
[tab][tab]- Aristotle

 

[bradcom]

Thank you for the replies. Based on your replies, here is some more information:

I went to the compaq site and found that the machine only supports 48mb's of ram. In fact, here are the memory specs:
-Maximum Memory 48MB
-Memory Slots 1 (1 bank of 1)
-non-removable base memory 16MB (not sure what this means)

I don't have another computer that I can test the ram sticks in, however I actually have 3 sticks. All 3 don't work (1-32mb, 2-128mb).

I'm taking the ram reading from the OS (properties of "My Computer&quot. I don't see anywhere in the BIOS where I can find the info, unless this is it:
System Memory: 640KB
Extendex Memory: 18880 KB

Hopefully that helps a little. Thanks again for the help.

 

[cdogg]

How many physical memory slots do you see on the motherboard? 1, 2, or 3?

It appears that since the max memory is 48MB, you can count the 128MB sticks as incompatible.

~cdogg
[tab]"All paid jobs absorb and degrade the mind"
[tab][tab]- Aristotle

 

[mjpollard]

The 'base' memory refers to memory that is permanently attached to the motherboard. Since the motherboard has a slot and the web site says it can take a 32Mb stick in that slot (hence the 48Mb max supported), we must deduce that the physical format of the 32Mb memory stick you have is not compatible with the Compaq. If you go to web sites where they are selling RAM you will notice information such as 16x64 or 32x8 given for the different sticks. This indicates the type of individual RAM chip used on the stick. On the three non-compatible sticks you have you can see the individual chips and usually you can read the markings and/or part numbers. In the time-frame that your PC is from there was also a problem with distinguishing between 'true-parity' and 'parity'.

For what it is worth, RAM may be the most difficult thing to purchase for an older PC, so I can feel your pain.