Coverage - Published on Wednesday, 27 July 2005 23:27 Written by Robert Kihlberg
During the first day at DreamHack it was time for us to see if the hardware was up to the task. The CPU had only been tested with air-cooled overclocking. With a P4 Prescott original cooler (copper core instead of just aluminum like in the Celeron-cooler), 4050Mhz was the highest SuperPi 1M stable speed. Despite the fact that there was 1 Ghz left to achieve our goal, we felt relatively safe knowing that we had access to temperatures 100 degrees lower and more stable voltages. This was done with an actual voltage of 1.55V during load. The first stage was to isolate the motherboard and assemble the compressor cooling. As we suspected the CPU responded well to the cold and with a temperature of -45C (temperature-sensor was placed against the integrated heat spreader (IHS) on the processor, read by a Fluke digital thermometer) we began to climb in the frequency-range. Because we didn’t want to be caught of guard we ran SuperPi 1M with a 50Mhz interval. With a vcore of 1.500V we reached a stable speed of 4600Mhz SuperPi 1M. At this point the CPU began to demand massive increases in voltage to remain stable. It took 1.650V to get through SuperPi at 4700Mhz. At this speed, combined with BH- 5 in 249Mhz, 2-5-2-2 and PAT fully activated, it took SuperPi 1M 35 seconds flat. It only takes a frequency of 3700Mhz for equal results with a P4. In other words we have performance differences between this budget-CPU and its bigger brother with more L2 cache.
Time to deal with goal number 1 – 5 Ghz. The voltage was changed in BIOS to 1.7125V which is the maximum and was then turned up further to get 1.740V for the CPU. This turned out to be enough to get past the magical limit. 5007Mhz to be exact.
After the compressor got some well deserved rest because of the heat in the hall (~28- 30C) and we got some well deserved pizza, we went after goal number 2 – 5066Mhz, in other words 100% overclocking. After an inspection of the CPU-socket, the cooling-head was assembled back in place and was tightened even harder this time. The voltage was turned up to 1.760V and the magical number was inserted into ClockGen. To our surprise, the CPU managed to keep sufficiently stable for us to take a screenshot.
Page 3 of 6