My mother wants me to part together her a computer, she wants one that when the grandkids go to her house, they can play games on, like WoW and fable and the like. But when they are not there she just wants to use it for pictures and burning DVD's and so on. So for my question. How noticeable is the jump from DDR400 to say DDR2 667? Cause i've been thinking about gettin her a mobo that can support both, but if its not that big of a difference then i will just stick with one that can use her old DDR400. Like the abit ip-95 can take ddr400 and ddr2 533, i think it is, not real sure right now. But would it be worth it to buy one that can support both?
Unfortunately, all the MBs I've seen that support both are pretty much low-end kludges with third-tier vendor chipsets. The MB you mentioned seems to be the same.
The answer to your RAM question is "it depends on the system." Core2Duo-based systems are easily and safely overclocked for major performance gains, and require DDR2-667 to DDR2-800 or faster RAM for good performance when OCd.
AMD 64 socket 939 systems still make good use of DDR-400 (or even DDR-500 or super-low-latency DDR-400 if you can find it). Since budget seems to be an issue in your case, I would strongly recommend going with a socket 939 system.
Here's what I would do:
<B>MB</B>: new/gently-used from ebay. As socket 939 nears the end of its mainstream life, many people are upgrading to C2D systems or closing out unsold socket 939 boards. I was able to get a lightly-used MSI K8N neo4 Platinum MB w/accessories for around $50 including shipping.
<b>CPU</b>: Budget alternative is a $20 Sempron (frequent deals at e.g. Tiger); higher-end would be AMD 64 x2 3800+ for around $150.
<b>CPU cooler</b>: OEM if you get a boxed processor; Arctic Cooling Freezer 64 Pro otherwise, which should allow some decent overclocking.
<b>Graphics card</b>: this will be the main determinant of gaming performance, so get something decent in the $150 range unless you want to go whole-hog (you can get x1950 cards for $250 now).
<b>RAM</b>: Your current DDR-400 RAM.
<b>PS</b>: It's important NOT to skimp here for stability and OC flexibility. You want good power on +12V2 for the CPU (and possible future CPU upgrade) and on +12V1 for the system, including graphics card. Here's something decent: http://www.newegg.com/Product/Product.asp?Item=N82E1681...