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KT-7 RAID, Athlon Thunderbird Gaming System Build
By Len "Viking1" HjalmarsonCPU and System Cooling
Abit has implemented a 3-phase power solution on the KT-7. With this implementation, six Metal Oxide Semiconductor Filled Effect Transistor (MOSFET) are used to dissipate heat instead of the four (known as 2-phase) used on other motherboards. Abit has done their part, now you have to do yours.
ThermalTake Chrome Orb
My first CPU fan was the chrome orb. This rather unique design fits well atop a Socket A CPU, even on the KT-7 where some fairly hefty capacitors reside quite close to the Socket. The Chrome fins don't spin, by the way. Only the fan in the center moves.
Perhaps because of its unusual appearance, the Chrome Orb has a very good reputation. It's cooling efficiency is only moderate, however, equivalent to the Global WIN FOP32. A better cooler is the Alpha PAL6035 and the ATTech CM25.
ATTech CM25
Surprisingly, the Chrome Orb moves 22 cubic feet of air per minute over its vanes at 5500 RPM, and the ATTech moves only 20 cfm at 5200 RPM. The ATTech unit is also quite small.
The difference is in material. Copper is a significantly better heat conductor than aluminum, and the difference shows in heat dissipation. At idle, the ATTech reduced the speed of my overclocked Thunderbird (at 900MHz) from 32C to 28C! Under load the difference was a full 3C cooler. The only improvement one is likely to make beyond that temperature is via active cooling. Note, however, that you do need good case ventilation to achieve these temperatures.
You also need some good conductivity between the cooler and the CPU. Previously I've used a compound supplied by 3dfxcool, but after studying the matter I discovered Arctic Silver. This compound is about 80% silver powder, and silver is a superior conductor even to copper! It's expensive at about $6 US per tube, and you can get it at www.coolerguys.com.
Cooling Chart
The Bottom Line
Every accountant warns you about the bottom line. In this case, though, it's all good news.
On the GeForce 2 GTS Combat Flight Simulator II scored 42 fps on my Celeron II system at 733MHz (1024x768@16). On the Athlon Tbird at 990 this became 58 frames per second! This was with full realism in the flight model and the graphic detail almost at maximum.
Chart
Running with 2x FSAA the scores were 31 and 45 respectively. Running with 32 bit color brought 33 fps on the Celeron II, and 41 fps on the Thunderbird.
Jane's FA18 gave me 10 fps on the 733 with all detail to the max at 1024x768 (on deck). On the Thunderbird, the score rose by 50% to 15 fps (FRAPS 1.2).
