INQUIRER Guide to Core2 X6800 overclocking

OK, A WHILE AGO, I got my "Cointreau wine set" too. This consisted of two (fresh, not vintage) bottles: E6700 at 2.66GHz and X6800 at 2.93GHz, both on the (vintage this time!) Intel D975XBX board, with BIOS updated to support the Core 2 Duo CPU series.

There wasn't as much excitement as it could have been, as my earlier expectations of Intel announcing a 3.33GHz Conroe XE running on 1.333MHz FSB, bulldozing the competition in probably every single benchmark, didn't materialise at the end.

By default, the D975XBX has aplenty of overclocking options in the BIOS - including forcing the FSB to do 1333MHz, up to 30 per cent overclock across the board, changing of multipliers on Xtreme series CPUs, and all that coupled with excellent Digital VRM section cooled by a nice set of blue-fin heat sinks.

We got a spare ThermalTake GoldenOrb II all-copper heatsink, to cool it and see how far it goes. Corsair's DDR2-800 CL3 low-latency 2GB memory kit provided the RAM, while HIS X1900XTX IceQ3 Turbo at 700MHz GPU and 1600MHz GDDR3 RAM was the graphics card of the day.

The initial test was simple - don't change anything, lower the CPU voltage to the lowest possible in BIOS (1.275 volts), change the multiplier, and see how far we go. The default set at 11, or 2.93GHz at 1,066 FSB, was fine, and installed and booted Windows fine as well - 48C CPU temperature. No issues there.

We changed the CPU multiplier to 12, or 3.20GHz clock and all went well again. Windows booted and, before any benchmarks were running, the temperature was 50C about five minutes into the (mostly idle) operation.

Now, to try the multiplier 13. 3.46GHz went up in BIOS, but Windows froze at the boot screen. I changed the voltage to 1.2875 volts, and Windows booted fully, the temperature shown was 52C - no benchmarks ran yet on any of the speeds. Now, multiplier 14, or 3.73GHz. I set the voltage to 1.3 volts this time, Windoze froze at boot screen again. Change the voltage to 1.312 volts? No use - Windows won't boot either.

Now, I changed the multiplier down to 10 (same as on E6700 standard Conroe) and ran the 20 per cent extra "burn in" - ie. FSB 1,280MHz and a resulting CPU clock of 3.2 GHz. Windows booted fine at 1.275 volts. Up the multiplier to "default" 11 or 3.52GHz CPU clock? Pushed the voltage to 1.2875 volts again, and Windows booted fine as well. Temperature of the CPU was 55C some 10 minutes after the bootup!

Well, a bit lower than the expectations, but still not bad. Again, these are the first production Conroes and B2 stepping is out already, further improving on the potential. They better do, because I got a strange gut feeling that AMD will accelerate its K8L series rollout, as much as possible.

Some initial benchmarks? Watch out for the Part II this afternoon, including the brief 4GHz boot-time fun with water cooling! µ