D-Link DIR-635 security

Since building my gaming computer i noticed that it was running far slower than it should. So i was told to try a clean boot (which worked amazingly!), however i noticed that in doing this the antivirus software didnt load (seems logical now i think about it!). So i enabled all the Linksys processes and startup program in the boot options so now it runs on startup. However this has had a noticable effect on performance (especially in Crysis).

Basically, i was wondering if my router's onboard security (i presume it has some, it cost £65!), is good enough to protect me when only gaming. If i was going to start downloading something or using the internet a lot i would reboot with the antivirus software active, but would it be safe for me to rely on the router when only gaming?

If it isnt safe to do that, is there a program which isnt as damn demanding as Symantec Antivirus? I have NOD32 on my laptop but dont know which is better and i was considering one of those Yoggie Pico things but they cost a fair bit so software would be better really.

Thanks

Rich

I have NOD32 on my laptop so ill try that instead of Symantec and see if its less demanding.

However what i really need to know is if its safe to boot without my antivirus when just gaming as all antivirus programs use enough resources to impact gameplay to some extent? I would restart it if i was going to download or use the internet a lot, but i need to know if my routers onboard security is fine when just gaming?