it's actually CMOS that you have to clear, if you're sure you're using the correct jumper, try removing the CMOS battery for about 5 mins.
My guess is that you're trying to connect to 1.4 beta servers with the final client, or vice versa. That seems to be the typical issue every time a new CS version comes out.
Some results have been hidden because they may be inaccessible to you
Show inaccessible results