If I want to run 8 ~ 9 servers on One Dedicated Server
What is the min of my server need??

8-9 servers??? Thats alot. I wouldn't go above 5-6
Even for 5-6 - GET ALOT OF RAM - NO LESS THAN 1GB,
get a FAST HD, get GHZ processor(s)

I have a buddy who runs a successfull gaming company...
He runs about 8 ports (servers) of 1 game (cs)per server w/ shared oc12 backbone.
Each game port has its own FTP, Admin panel and NO one cept him can reboot servers!! (never give them that access)

His System config is:
Dual amd XP1900's
1gb DDR Ram
Ultra Scsi Hd's (super fast not sure exact model)
T1000 network card to backbone.
Redhat 7.3 OS (IMHO and his MANDATORY)
Win2k server (4-5 ports per box)

He can run upto:
8 of CS servers of >16 player limit
and it goes down on max ports when player limits raise.

HTH

how do u make money when running a cs or any game server?

you sell them to people by the month for some good cash.

i dont mean selling the servers...i mean by actually running them...besides donations...is there any other source?

you would need to sell..how else, by in-game advertising????

My buddy has it set to a certain $ amount per player on port..
amount x players = total price per mnth

He also does in game advertising via Admin Mod.
Also he list his site name in every servers name..
(ie.. Texas Counter-Strike -=Hosted by ApexSun.com=-)

To make any money on this you would have to charge per port!
or you could include a decent 200meg / 2gb bw webhosting account and incorprate costs of both into 1.
(I would not suggest webhosting and game servers off same box) [Even tho you can easily get away w it for a bit, most game severs will have stats and those can take up some resources when parsing larg log files. Therefore making the game servers lag when these run.]

HTH :D

Well, I suggest running a max of three CS servers on the machine you specified above.... How many max players per server he has set-up ?