You do need a crossover cable from the pc to the PS3.
Im assuming the router that you have only has one network port? as it'd be much easier to have a router with enough network ports so that you can plug ur PS3 and the PC into it. That way you dont have to rely on the Pc to be on so that ur PS3 is served internet.
How ever i believe you need to bridge the connections from the router to the PS3. You can do this by highlighting the two connections and rightclicking and then select 'bridge connections'. This is needed as a normal PC does not provide DHCP or DNS, you need to bridge the connections so that the DHCP and the DNS the router is serving, bridges across to serve the PS3 too.
You see i thought that because same applies for the 360 its just i read a thread on a forum at least 70 post long and each time it said crossover cable so took it as gospel...
i'll give the normal rj45 a try when i get home.... cheers peeps
That may be quite true.... but i have no need for a wifi router i dont have a Laptop with Wifi or anything else so that would be an expense that i dont need... having the ICS setup has served me well with the 360 just hope i can get it to work....