X-bit labs

AMD Athlon 64 3800+ CPU: E3 Processor Core aka Venice at the Door (page 12)

Category: CPU

by Ilya Gavrichenkov

[ 04/03/2005 | 04:06 PM ]

Overclocking

Right now AMD is not manufacturing any CPUs on Venice core with the clock frequencies over 2.4GHz. However, this is just for now. AMD believes that the new core manufactured with Dual Stress Liner and SOI technologies will allow increasing the working frequencies of Athlon 64 processors up to 2.8GHz. So, I would expect the frequency potential of the new Venice based CPUs to be pretty high.

According to statistics, Athlon 64 processors based on Newcastle core can be overclocked up to 2.6GHz on average. The same CPUs on Winchester core overclock about the same, although if you are lucky enough you might find a better sample, which will be able to reach 2.65-2.7GHz frequencies. We expect the new Athlon 64 on Venice core to become the record-breakers today.

Well, for our overclocking experiments we took an Athlon 64 3800+ on Venice core marked as ADA3800DAA4BP. The nominal clock frequency of this processor equals 2.4GHz, and the core voltage is 1.4V.

The overclocking tests were done on the following testbed:

• DFI NF4 Ultra-D (NVIDIA nForce4 Ultra) mainboard;
• AVC Z7U7414001 cooler;
• Corsair CMX512-4400Ñ25, 2 x 512MB RAM;
• PowerColor RADEON X800 XT graphics card;
• Maxtor MaXLine III 250GB.

Since Venice based processors, just like their predecessors, support Cool’n’Quiet technology, the clock multiplier can be reduced below the nominal value. However, we carried out our first overclocking tests without resorting to this option.

First of all, we decided to check how far our Athlon 64 3800+ on the E3 core stepping could go without raising the Vcore. Here we managed to raise the clock generator frequency from the nominal 200MHz to 226MHz. In other words, the processor working frequency got 2,712MHz. The CPU overclocked up to this point worked stably and went through all the benchmarks including Prime95 and S&M stability tests. So, without much effort we managed to reach the frequency unattainable for most Athlon 64 processors on D0 and CG core revisions (without any additional cooling involved).

But we didn’t want to stop at this point, of course. We also wanted to see what height we could reach once we increase the processor Vcore. That is why the second overclocking attempt was undertaken once we increased the Vcore by 13% over the nominal value, i.e. up to 1.58V. In this case the top frequency limit our processor could work on stably got much higher. We managed to make our clock generator work at 240MHz, thus bringing the processor core clock up to 2,880MHz. At this frequency our CPU run through all the tests flawlessly again, but the frequency couldn’t be raised any further without losing stability.

The screenshot below proves how far we reached: