Want to upgrade memory to 2 GB. Desktop will not post up with 2x1GB cards. Every 2-3 seconds it makes a sound/tone. The fans would turn on but there is no signal to the monitor. However, it will post up with 1x1GB card and 2x512MB cards. Seems like the desktop needs to be reset to recognize 2GB memory? How do I reset the desktop?

There is no reset just because you added memory.

If you have 2- 1GB sticks, try both , one at a time.

Your system spec's and manual tell nothing which dimm banks are suppose to be used , and if you can install 2-1GB sticks,
all it says is it can handle 2GB.

Now it says 512MB, sticks, this could mean you can only use 4-512MB sticks to get too 2GB,.

Now it does not tell which dimms are used if you have 2-1GB sticks,

You have 4 slots, the first two and the second two, most times, you either use the second bank of each pair, or the first slot of each pair,
but as I said, your system does not say.

So you can try both ways and see if one of them work.

Sorry I can't be of more help,but you system has a poor manual
on memory placement.

Hi,
The maximum memory that this desktop can accept is 2GB. Please make sure that the 1GB ram modules are PC3200, 400Mhz, DDR400, 2.5v. These are the only 1GB modules this computer can accept.

Sounds like you have the wrong RAM installed - make sure you have matched pairs of PC3200 DDR SDRAM. (333mhz).

OR one of the sticks is faulty. Try using just 1 at a time. If this works, then they are not matched (Speed, Read/write speeds..)