mac mini ram upgrade problems

I have a mac mini 2.0 GHz intel core duo mac mini. I used to have 2 512MB memory modules installed for a total of 1GB. I wanted to go up to 3GB (which I have read is the maximum) so I bought 2 x 2GB memory modules. I have installed both of them and booted the system and ran "free -m" from the command line to see how much RAM I have now. It still says I only have 1GB! I ran dmidecode to see what it thinks it has and got the following:

Physical Memory Array Location: System Board Or Motherboard Use: System Memory Error Correction Type: None Maximum Capacity: 4 GB Error Information Handle: Not Provided Number Of Devices: 2

Handle 0x0120, DMI type 17, 27 bytes Memory Device Array Handle: 0x011F Error Information Handle: No Error Total Width: Unknown Data Width: Unknown Size: No Module Installed Form Factor: DIMM Set: None Locator: DIMM0 Bank Locator: BANK 0 Type: Unknown Type Detail: None Speed: Unknown Manufacturer: Not Specified Serial Number: Not Specified Asset Tag: Unknown Part Number: Not Specified

Handle 0x0121, DMI type 17, 27 bytes Memory Device Array Handle: 0x011F Error Information Handle: No Error Total Width: 64 bits Data Width: 64 bits Size: 1024 MB Form Factor: DIMM Set: None Locator: DIMM1 Bank Locator: BANK 1 Type: DDR2 Type Detail: Synchronous Speed: 667 MHz (1.5 ns) Manufacturer: 0xCE00000000000000 Serial Number: 0x9353074D Asset Tag: Unknown Part Number: 0x4D342037305432383634515A332D43463720

I tried removing one of the 2GB sticks and it still comes back with the same thing. Does anyone know what I can do to get these working? Thanks.

One time I put a stick of ram in and it didn't show. I put it a couple of mor times and sent itn back. The guy tested it and said it was good. I put it in again and it still didn't show . The last time I put it in I finally got it seated correctly and it showed and has been working for two years. Maybe yoou should check it real good.

Looks like Dimm0 is not seated all the way, and the other card is only 1GB. You might want to make sure you got the right sticks of RAM.

Also, Macs can be particular about RAM. If you just bought some inexpensive RAM, it is likely that the Mac will not like it.