Low server's fps

When i starts server before (about 1 year) server runs normally with 30 players on it and has around 150 fps. Now it has 60 fps without players and 33 fps (all time) with 1 player. And i’ve got a lot of lags when i spawn some entities.
fps_max is 300

Here is my server.cfg



hostname         	"meow"
rcon_password    	""
sv_password      	""
sv_region        	4
sv_lan           	0
sv_logbans       	1
sv_logecho       	1
sv_logfile       	1
sv_log_onefile   	0
sv_noclipspeed   	5
sv_noclipaccelerate	5
//Sandbox Settings
sbox_allownpcs  	0
sbox_godmode     	0
sbox_plpldamage  	1
sbox_playergod   	0
sbox_noclip      	0
sbox_maxprops    	50
sbox_maxragdolls 	0
sbox_maxnpcs     	0
sbox_maxballoons 	0
sbox_maxeffects  	25
sbox_maxdynamite 	0
sbox_maxlamps    	0
sbox_maxthrusters	0
sbox_maxwheels   	0
sbox_maxhoverballs	0
sbox_maxvehicles 	0
sbox_maxbuttons  	0
sbox_maxsents    	0
sbox_maxemitters 	0
sbox_maxspawners 	0
sbox_maxturrets  	0
//Server Settings
net_maxfilesize  	30
sv_minrate       	0
sv_maxrate       	2500
decalfrequency   	15
sv_maxupdaterate 	33
sv_minupdaterate 	10
//Execute ban files
exec banned_ip.cfg
exec banned_user.cfg


Start options:



-console -game garrysmod +gamemode sandbox +map gm_construct +maxplayers 10 +sv_kickerrornum 0 -tickrate 33


Machine where server runs:



Windows 7 64bit
Intel Core I7-3820 3.6 GHZ
16gb RAM
GTX 580 Ti


Your server’s FPS is 33 because you have tickrate set to 33.

But why i’ve had more 150 fps before? Tickrate was default.

[editline]1st April 2016[/editline]

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