Wut is up with my LAG on CS!!!

Hp pavilion 533w
Windows XP Home
2.0ghz intel celeron
120gb western digital hd
256 Ram
Lan

Alright...I just put in a new hard drive because the other one was defective and now when I play cs I get lag every 10 to 15 seconds or so. Its not my internet connection because I have never had this problem before. I have messed with all the rates in the game and that isnt helping either...I dont have any loss or choke during play anyways. I know that I put in the hard drive right, but i dont know if that could be the cause of the problem or not...kinda doubt it. I had been messin with my cs config quite a bit so I dont know if I screwed something up in there, but if there is a console command for returning everything to defaults I would appreciate that. I have even deleted steam and reinstalled and that didnt help. Seems like I have tried everything so take your best guess....I am clueless.