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Test System and Overclocking
Keep in mind that during overclocking, the latencies are as follows: CAS-TRCD-TRP-TRAS
Because the memory focuses on low latency, all tests will be conducted with timings of 2-2-2-5. There isn't really a point in checking speeds at looser timings, because that's where TCCD shines. If enthusiasts wanted looser timings, they wouldn't have paid up to $400 for old BH5's a year ago. Testing will focus on speeds at different voltages. The DFI Ultra-D can supply up to 4v to memory, so we won't have any bottlenecks in this department.
While the memory is rated to need 2.8v, I proceeded to find the lowest voltage it actually needed. With just 2.6v, the Gold PC3200 was able to run the rated speed and timings. Unfortunately, it didn't overclock very well with such low voltage. A slight bump to the rated 2.8v allowed operations at 220HTT. That's a pretty decent result. Enthusiasts limited to 2.8v will get a small overclock. The next jump in voltage was 3.2v, which is generally the highest VDIMM a motherboard allows. The results went up another 15MHZ to 235HTT. Not too shabby. Although it isn't stunning like the old BH5's, it's still great, considering that the memory did not go through a burn-in period. We all know that BH5 chips can obtain better results after some serious burn-in, but this review can't wait that long. Another jump in voltage to 3.4v resulted with another 10MHZ increase to 245HTT. 3.4v is generally the motherboard limit when enthusiasts decide to use the OCZ DDR Booster. With no barriers, I gave the memory as much juice as I could. For some reason, the motherboard goes flaky after 3.6v, and so the highest VDIMM supplied was 3.6v. The memory reached its limit in my system and provided a great low latency frequency of 255HTT. I knew it was the limit because I have other sticks of Winbond UTT BH5 chips that were able to do 265HTT with 3.6v. Granted those were lower in chip density, but it proved that nothing in my test system was a bottleneck.
If you would like to see low latency results compared to the high frequency TCCD, check out Randy's review of the OCZ Gold PC4000 VX, which are based on Winbond UTT CH5. In there, he compares the performance of low latency at a divider against the TCCD at 1:1 ratio, both with the same exact CPU speed. Remember that 300MHZ TCCD at good timings are quite hard to find, and these Winbond UTT chips are being mass produced. Although TCCD is still the better performer at 1:1 ratio, these low latency chips can certainly keep up with a divider.