Thanks for all the input. Unfortunately, the conclusion is that something is wrong, but we don't know what. It is probably with AC, but I guess I have to include the possibility there might be something wrong with server or network setup.
Thanks,
If there was something wrong with AC, everyone would have the same issue. My gut tells me it's related to your storage. What types of drives store your AC Database? It's not a RAM issue since as you said it doesn't break 3GB. The Processors are also pretty good assuming you have allocated enough to the VM. The only thing that isn't clear is what drives and what RAID level. I would consider moving to SSDs as it sounds like your Amazing Charts installation is accessing the disk more than accessing the cached pages in RAM.