The ram type was listed on my invoice. Where it lists the amount of ram, it should also list the type. If you have pc600 and you are within your 30 time period (from invoice date) you should be able to swap out the ram with pc800 and you only have to pay the difference in cost. I missed the time frame myself. I believe it is $70 for 128 meg. You may want to post this question in the customer service section under GENERAL, or talk to a service rep.

I had a high pitched sound that was coming from my 8100 as well. I could hear it across the room. Tech support sent out a new power supply and the tech that installed it said that there may have been a fault in one of the transistors...he named it but unfortunately I dont remember. There is still a sound, but it is very slight, I have to put my ear next to the box to hear it.

You should give tech support a call.

Hope this helps!

Eric