The first thing you should do is pull out both sticks and check the information listed on both. What are their rated speeds, timings, and voltages. For DDR you should see speeds listed in either bandwidth (PC2100, PC2700, PC3200) or clockspeed (266, 333, 400) notation. Your board supports the 2100/266 and 2700/333 speeds but does not list support for 3200/400 RAM, so it is possible that you have mis-matched RAM modules and your board cannot run with both modules installed. The other possibility is a timing mis-match, but desktops aren't nearly as picky about this as laptops so I don't think you have to worry here. Regardless, make sure the CAS latency is also identical on both sticks. CAS latency is the first number in the list of timings. Most memory modules have 3 or 4 numbers listed for timings, in x-x-x or x-x-x-x fashion. For DDR, common ratings would be 2-2-2, 2.5-3-3, and 3-3-3. Again, the first number is the only truly relevant number WRT compatibility. Lastly you have voltage, which for DDR should be in the 2.5-2.7V range, and will be listed as such on each module. If you cannot find this information printed on a sticker attached to your RAM it could be difficult to find so let me know if you don't have this information sticker on your RAM modules. Once you've verified specifications of each memory module, try swapping them. If you have the 1GB module in the slot closest to the CPU now, try putting the 512MB module in that slot instead and moving the 1GB module over. If the opposite is true, reverse these instructions.Beyond this point if your system still only has at most 1GB RAM, you will probably have to replace that 512MB stick with a 1GB module which is identical to the one which you already own.Hope this helps!

Hi,Take a look at the memory yourself....use pw: pairingproblem Tried swapping no change...how about the BIOS I tried...how can I tell if it worked and updated correctly?Berne

Hi,Take a look at the memory yourself....use pw: pairingproblem Tried swapping no change...how about the BIOS I tried...how can I tell if it worked and updated correctly?Berne

I believe this is a density problem. The older stick has 2 ranks of memory modules whilst the newer has only 1. Your motherboard probably doesn't like this combination. So despite not "needing" matched memory modules, your system needs matched memory modules :( Looks like you'll have to get another 1GB stick identical to the current one in order to run >1GB RAM on that motherboard.

Hi TechguyMaxC,I was almost certain and now I am.All the best,Berne :(