The Athlon XP 3200+ is the latest incarnation of the Barton core, and physically, is a dead ringer for the Athlon XP 3000+. There have been no architectural changes with the new 3200+ model, and it sports the same 128K L1/512K L2 cache, die size (0.13-micron) and transistor count as the other Barton core models. That is not to say there have not been changes with AMD's newest powerhouse, but only that these enhancements relate more to platform support and performance.
The first enhancement is the processor clock speed, which has been upped to an even 2.2 GHz for the Athlon XP 3200+. This is only a nominal increase from the 2.167 GHz of the Athlon XP 3000+, which on the surface, doesn't add up to the 200-point jump in model numbers. This brings us to the second major improvement, the 400 MHz front-side bus/200 MHz system bus. This brings with it an increase to overall CPU and system performance, while also raising the bar to synchronous DDR400 memory. These factors, added to the slight jump in CPU clock speed, help justify the Athlon XP 3200+ model number.
The new 400 MHz FSB brings with it some definite benefits, and in some ways, offers performance for free. AMD has basically raised the core speed by a miniscule 33 MHz, but increased the FSB by a more significant 66 MHz, and put the onus of the performance gain on the platform and memory, rather than increasing CPU speeds. This is what you call a "quick win", where an architectural enhancement allows higher performance levels at the same basic CPU clock speeds. The only catch to this plan is that certain benchmarks, applications and games really don't scale that well to higher FSB speed, and instead rely on pure processor speed.
AMD has a wide range of Athlon XP models, so here's a chart that should help sort them all out and differentiate between the various core designs and front-side bus speeds:
Since the Athlon XP 3200+ makes use of the 400 MHz FSB, platform support is of the utmost importance. NVIDIA has already announced a new revision of their nForce2 chipset, dubbed the nForce2 400, which comes in two distinct products. The nForce2 Ultra 400 is similar to the current nForce2 SPP, and supports dual-channel DDR400 and all the other fixings. The lower-end nForce2 400 shares the same architecture as the nForce2 and nForce2 Ultra 400, with one important distinction, the standard model includes only a single-channel DDR memory controller. This is obviously market-driven, and will allow NVIDIA to hit the mainstream vendors with lower-cost nForce2 400 parts, while keeping the enthusiasts happy with their dual-channel DDR400 goodness.
VIA has also announced 400 MHz Athlon XP support with their KT600 chipset, which includes support for DDR400 memory. In terms of current motherboards, many vendors have been using 400 MHz-compatible nForce2 parts in their newest revisions, and the AMD website lists nForce2 motherboards from ABIT, ASUS, Chaintech, Leadtek and MSI as being certified for use with the Athlon XP 3200+. Expect this list to grow as the weeks pass by.