History: Protection Against Thermal Death
About a year ago, THG stirred up quite a commotion in the industry with its article Hot Spot: How Modern Processors Cope With Heat Emergencies . Accompanying the article was the very first downloadable video, which shows the dramatic behavior of an AMD Athlon with a Palomino core, equipped with a thermal diode, when the CPU cooler fails during operation.
The alarms sounded at AMD, and the THG crew met several times with engineers from the manufacturers in question (AMD and Siemens). A few weeks later, AMD introduced a new circuitry logic to a small group of people. This was supposed to turn off the power supply as soon as the die temperature surpassed 85 degrees Celsius.
In order to guarantee faultless protection, the CPU temperature is measured by the thermal diode in very short time intervals, which ensures that the power can be switched off in time. Currently, all motherboard makers have a copy of the new "Thermal Guide" from AMD.
Comparison: T-Bred "B" Vs. T-Bred "A" Vs. Palomino
| Processor core | Number of layers | CPU classes |
|---|---|---|
| AMD Thunderbird | 6 | Athlon 650 MHzto 1400 MHz |
| AMD Palomino | 7 | Athlon XP 1500+to XP 2100+ |
| AMD Thoroughbred "A" | 8 | Athlon XP 1700+to XP 2200+ |
| AMD Thoroughbred "B" | 9 | Athlon XP 2400+to XP 3000+ |
| Processor (Thoroughbred "A") | FSB frequency | Clock frequency | Model Number |
|---|---|---|---|
| AMD Athlon XP 1500+ | 133 MHz | 1333 MHz | 1500 |
| AMD Athlon XP 1600+ | 133 MHz | 1400 MHz | 1600 |
| AMD Athlon XP 1700+ | 133 MHz | 1466 MHz | 1700 |
| AMD Athlon XP 1800+ | 133 MHz | 1533 MHz | 1800 |
| AMD Athlon XP 1900+ | 133 MHz | 1600 MHz | 1900 |
| AMD Athlon XP 2000+ | 133 MHz | 1666 MHz | 2000 |
| AMD Athlon XP 2100+ | 133 MHz | 1733 MHz | 2100 |
| AMD Athlon XP 2200+ | 133 MHz | 1800 MHz | 2200 |
| Processor (Thoroughbred "B") | FSB frequency | Clock frequency | Model Number |
|---|---|---|---|
| AMD Athlon XP 2400+ | 133 MHz | 2000 MHz | 2400 |
| AMD Athlon XP 2600+ | 133 MHz | 2133 MHz | 2600 |
| AMD Athlon XP 2700+ | 166 MHz | 2166 MHz | 2700 |
| AMD Athlon XP 2800+ | 166 MHz | 2250 MHz | 2800 |
| AMD Athlon XP 3000+ | 166 MHz | 2xxx MHz | 3000 |
With the launch of the Thoroughbred core in the "B" version, AMD Athlon reaches the fourth level in its evolution. After the K7 in 1999 the first core with integrated L2 cache, the Thunderbird, was introduced about two years ago. AMD made a further step in October 2001 by introducing the Palomino core, which essentially consisted of the SSE command set expansion and optimized cache lines.
The Thoroughbred core has been around since June 2002, and this one involves a rearrangement of the CPU's internal components, as well as smaller structures (0.13 micron). Detailed information is given in the table below. The animated GIF graphic gives you an idea of how the size has changed with the individual CPUs. In order to give you a complete picture, we've included the data for the Barton core, which is expected to be out in Q3. The Barton represents the fifth and last level of development of the Athlon program, based on Socket 462.