I'm putting an HTPC together I have the following:
1. X1800XT Sapphire
2. Antex Ns2400
thats it. What else should I get. Give some suggestions please.
I'll watch movies and play games. Is this a good cpu for my purpose?
Thanks
This CPU will not pass the HD muster test --- and contrary to what you saw above, will under perform the 3800+. Typically cache is not as large of an affect on the AMD architecture, but going from 512 to 256 KB is significant as the cache miss rate is inversely proportional and not directly linear with cache size. That is to say, 256 to 512 is a bigger gain than 512 to 1 Meg in cache.
I am assuming you are cost conscious by asking this question, it would be worth holding off a month or two and saving up money to go up to a 4400+ or a C2D E6300 (if you are not advserse to Intel).
Also, paired with your proposed graphics card, you will likely end up throttling at the CPU and it would be a waste to use this card with the 3600+. If you commit to a 3600+, get an x1600 or an nVidia 7800 series card. (Anand tech just did a good review of HDCP compliant cards, you may want to take a look).
I have sen this Sempron 2600+(S754) with a 128 L2 clocked as an Athlon with 512 and one with 1024 and the top difference with the 1024 L2 model never grew beyond 13% (in games only) with an average of 4-5% and that is 128 to 1024 so 256 to 512 should be much less.
http://www.xbitlabs.com/articles/cpu/display/sempron-2600_4.html
Agree with you that 512 L2 gives the best results and AMD itself has turned all they future athlons on 512 L2 only.