Can hdd bottleneck dude server?

In time my dude server began to work a bit slower. When adding device it freezes for few seconds, or cant read and cache some svg icons for some time.
I have about 10 maps 300+ devices, ant 2-6 probes for each device. There are about 150 mikrotik devices, and some data from them is logged, likw ping, http time, link speed and so on.
Hardware is Pentium D 2Ghz, 2Gb ram 160Gb seagate.
So in winbox or shell i can see about 6000 sector writes per second (973 701 522 since reboot 28days ago). I think this hdd can’t keep up with dude.

Do anyone had, o has same problems? Do anyone knows, how many writes per second modern sata hdd’s are capable?

I will add about as much devices in half year, so i want to be sure, if it will work ok.

I’d throw ram at it first then go to toms hardware and check out the disk benchmarks if ram doesn’t solve it…

this is my graphs:
weeklycpu.gif
weeklyram.gif
weeklyhdd.gif
Also it makes about 500~ connections, most are mikrotik connections, and http, ssh connections. I have lovered time_wait timeout because i had about 3k connections with time_wait state.