want to buy a vps，and what is the basic system requirements

[takenpuppi]

I want to purchase a cloud server and didn't know how many nodes to buy.
Each node include a 0.6GHz CPU, 376RAM and 15GB disks.
I want to have a Mantis for 50-100 people to use.And may be 300 people to use in the future.

Is there any advices that how many nodes need to buy.

thanks.

[atrol]

You don't have to know the number of users, you have to know the number of issues per day and the number of parallel working users you expect.
It depends also on the operating system you use.
If you use a 32 Bit Linux like Ubuntu 10.04 LTS I guess that 2-3 nodes are enough concerning CPU and RAM.
If your users are adding a lot of attachments you might get disk space problems after a while.