HLDS Terrible performance

[wowwen]

Hello everyone.

I have terrible performance issues on one of my servers. The other servers are running srcds and goes smooth and nice.

For starters:
Hardware:
Intel core 2 duo E6850 3.0ghz
2gig ram
120Gb 7200rpm disc

Software:
Ubuntu 8.04 LTS
Modded kernel -> 2.6.24.4 1000Hz RT

Connection:
With my recent readings 80/80Mbit

This is in my opinion a fairly good server. Its perpose is to run ONE server. A standard Condition Zero server.

Command line options:
pingboost 2 sys_ticrate 600 26 players

Cfg setting:
fps_map 600
sv_maxrate 20000
sv_maxupdaterate 70

Problems:
The server chokes terrible, if a take a look at the server fps, it pends up and down, from 120 to 500. I dont know if that creates the choke. This even happens with 4-8 players.

If i lower the updaterate to 30, the choke is pending from 1-10, but this isnt the settings i was hoping for with the hardware the server is running on. The really strange thing is that the server dont top the cpu load at all, i cant push it over 30% load according to "top". And thats with sys_ticrate 1000 and pingboost 3.

What have i made wrong, what have i missed ?

Sorry for my bad english

Thanks in advance