AMD 1.2 GHz Athlon compatible with PC100 RAM?

The RAM have nothing to do with the CPU.

The only constraint is the mobo chipset. ie if you have a mobo that only uses SDram and that it can support PC100 and PC133 then you are fine.

If the mobo chipset only supports DDR, which should be the the out-coming new ones then you will need to get DDR ram.

Conclusion, first you choose the CPU, then you choose the mobo that is compatible with your CPU, finally find out what RAM the chipset on your mobo support and done.

Usually you want to make sure everything is the newest and fastest on the 5 most important component in the PC
1 CPU
2 RAM
3 Graphics (for gamers, non gamers can skip this)
4 mobo (deciding factor is chipset)
5 HDD

This list always stick to this decending order, because like everyone else you want the fastest CPU, and then you want the fastest DDR266 with least CAS value. 3rd you find your fastest Graphics and 4 you find a mobo that support all of those, and finally the HDD is the last bottleneck to destroy.

I personally would change to DDR266Mhz, it will be a extra boost your Athlon 1.2G, think of it as a Turbo to your existing 2.0 V6 Quad cam type of car.

Since SDram price drop by 50% and DDR price will come out like SD's price, it's a good deal.

Best regards
cx5

Thanks people, I had absolutely no idea that the mobo was the deciding factor. I guess I'll just get DDR RAM so I can take full advantage of the 1.2 GHz of Athlon power.