Hello Everyone, I am having problems when I play Counter-Strike Source.  It seems to be skipping or lagging every 30 seconds or so. Sometimes less then 30 seconds and sometimes more. It seems like lagging but when I check my latency it is perfect with no spiking at all. I play on another computer in my house and it doesnt do that at all. It is more of a skip not a lag. At first I thought it might be my graphics were to high. So I turned my settings all the way down and it still did it. I have played this game for years and it NEVER did this till recently. I decided to upgrade my graphics card and it still didnt help. I had 1 gb of ram so I decided to buy 2 more. So now I have 3 gb and it still does that same thing. I have turned my refresh rate all the way up on my monitor and it doesnt work either. This game has always worked until now. I thought reformatting my computer would help but NOPE. Buying a new hard drive didnt help either. I have downloaded all the new windows updates and driver updates. I went to my video cards website and downloaded the most recent update. Still NOTHING. Can anyone help me please or offer any ideas.  
Thanks  
 

Woah. If your game goes slow unexpectedly don't just go and buy new hardware, there is obviously a problem you have to sort out.
You will get far better responses on forums.steampowered.com. Do a few searches there. I will give you the basics though.
 
First of all. Bring up the console in-game and type 'net_graph 1'. Are you getting any loss/choke?
 
Do a video stress test.
 
Try another online game. How are your FPS and Latency?