[droubal]

I bought an Acer Desktop with 1 GB of RAM. I noticed that it only shows 768 MB of Total System RAM in System Information. It should have shown 1024 MB.

I purchased and installed 4 GB of new RAM of the type recommended.

Instead of 4.096 GB it shows 2.815 GB
I asked Acer about it but got back a message that it was showing me less because Windows took up the rest.
That doesn't seem correct. Total system RAM should be the whole amount.

Any ideas how I can find the missing RAM?

[Hybr!d]

Sounds like originally your onboard graphics card was taking some RAM to work.

1024 > 768 = 256 going to the GFX card.

Then you added 4096 but 32bit Windows can only see 3100ish.

2815 + 256 for the GFX card = 3071.

So, in short you need 64bit Windows to unlock the rest.