Standard DRAM Memory

[upnrunin]

I'm trying to keep two old HP Pavilions running well by appropriately upgrading the memory.  I have an xt983 which according to the HP site has a maximum memory of 512MB.  The crucial site said the max was 1024MB?  I had bought a Crucial brand 512MB card locally and added it in the second slot.  After a few boot ups the system crashed.  I've restored the system but am concerned about how to correctly expand the memory.  Also, I've noticed there may be several memory cards with the same specs but will have different part #s and prices.  The one I bought locally was a different part # than the Crucial site recommended (but all the specs matched).  I know one mistake might have been adding the 512 behind the factory 128.   I open to expert advice??

On the same note my other model is a xt948.  HP list the max at 1.5GB with a recommended 512MB.   I don't know whats best based on that.

These are PC133 (168 PIn DIMM) although the HP site says the xt983 "(runs at 100)".  Hope this makes sense.

[Crucial_maulmod]

When you order online by system information, you are shown what we refer to as an “external” part number, in your case numbers CT236367/ CT260510. It is a system specific number and is mapped exclusively to the HP Pavilion XT983 Series. The longer part number, is the one that would you see printed on your module, and that is the actual module part number, or the "base" part number.

There are other specifications to memory than the basic ones published on the site, and they sometimes requires us to filter out a certain build of a part for a specific system. The external part number can accomplish this, since we can build filters into them when necessary. Those filters are also the reason that we can only guarantee compatibility if you order by system; the external part number tells us which computer you are ordering for.

Let us know the full CT part number from the module and we can confirm it's compatibility.

We do recommend a 1GB maximum for this system but it is possible that the manufacturer released two versions and some can only support 512MB. 

Please try the new 512MB on it's own in the first slot to see if you get the same problems.  We also recommend that the largest module is installed in slot one anyway so swap this and the original around.

You can also check that you have the latest version of the BIOS for your motherboard from the manufacturer's website.

The XT948 should also be able to support 512MB per slot, it has three slots to reach the 1.5GB maximum.

With regards to speed, generally speaking, memory is backwards compatible so you can install faster memory but it will run at the slower speed.