Memory performance
If you've seen our memory performance tests before, these graphs and scores will look very familiar to you. In truth, nothing has really changed, memory-wise, with the latest speed ramp of the Athlon. Its DDR memory still performs pretty much the same as before. Below is a Linpack graph. If you're not familiar with how to read one, go here for an explanation.

Linpack actually measures memory access to the L1 cache, L2 cache, and to main memory. The left half of the graph, roughly, shows how the caches perform, while the right half deals with large enough data sets that main memory is primarily involved. As you can see, the 1.4GHz Athlon's on-chip caches are indeed faster than previous Athlons. At about 64K, the Athlon's L1 cache performance peaks, and it's much higher than the Pentium 4. Once we get to about 192K, we're well into the L2 caches, where the Pentium 4 is faster. And out on the right half of the graph, above 320K, we're measuring memory bandwidth. Here, as always, the Pentium 4's dual RDRAM channels whup all comers. All of the Athlon DDR scores bunch together, and just below them is the PC133-based Athlon/Via KT133A combo.

For another perspective on the same thing, let's look at how SiSoft Sandra's Stream test measures memory bandwidth.

Once more, the P4 wins the memory bandwidth contest. That probably won't begin to change until the Athlon T-bird finally retires, and the Athlon Palomino (found in the mobile Athlon 4 and the multiprocessor Athlon MP) takes over for it.

But, as always, these memory bandwidth tests are quite theoretical. Let's see what happens when the rubber meets the road...