Memory prices have fallen dramatically over the last six months. These days it is not uncommon to find a generic stick of 512MB PC3200 DDR memory for about $60 CDN. Yet over the same time period, enthusiast-calibre memory has not fallen in price much, unfortunately.

Take for example OCZs PC4800 Dual-Channel Platinum Limited Edition kit of two 512MB sticks of DDR. Aimed directly at the performance user, these puppies have a retail price of $330 CDN ($265 US). Quite expensive compared to the average stuff that's on the market, but by default this DDR is rated to run at an amazing 300 MHz with 2.5-4-4-10 memory timings (at 2.85V)! The timings are pretty quick, but not quite at the level of 2-2-5. Still, DDR600 is definitely an impressive feat and tight timings are not as important to the AMD Athlon64 as they are to Intel Pentium 4 systems.

OCZ present its PC4800 DC Platinum LTD Ed memory in jackets of nickel-plated copper heatspreaders. Realistically, heatspreaders don't do much for cooling at lower speeds/voltages, but they do a good job at protecting the memory from physical damage. If you plan to really overclock your memory, its also generally advisable to actively cool the DIMMs with a small fan.

OCZ PC4800 DC Platinum LTD ED

Overclocking to DDR600 Levels
Before we began to push the OCZ PC4800 DC Platinum LTD Ed memory modules, I first lowered the CPU multiplier to 6x; this way the CPU will not be the bottleneck holding the memory back. If you haven't guessed, I'm a low latency freak and I was interested in seeing how high the PC4800 DC Platinum LTD Ed memory would run with 2-2-2-5 memory timings.

Starting at stock speeds with a voltage of 2.6V, I increased the motherboard speed in ~5 MHz increments. The first blip hit at 221 MHz; at that speed, the memory started to become unstable and would often drop back to desktop while running 3D applications.

Overclocking Results:

memory timings: 2-2-2-5 2.5-4-4-10 memory speed: 234 MHz 318 MHz If you're new to Overclocking and not sure what to do, check out these two excellent Guides for some pointers: Overclocking the CPU and Memory Overclocking the Videocard

Increasing the memory voltage moderately to 2.8V solved those issues and I continued to push the memory further. With tight timings, the OCZ PC4800 DC Platinum LTD Ed finally topped out at a very respectable 234 MHz. Increasing voltages (up to 3.8V) did not garner higher stable speeds but still, 234 MHz with 2-2-2-5 timings at 2.8V is very good!

Lowering the timings all the way down to 2.5-4-4-10 (the memory's default) I continued going up from 234 MHz with 2.8V. Amazingly, the memory simply flew at these settings and the PC4800 DC Platinum LTD Ed easily hit its default rated speed of 300 MHz! Moving past 300 MHz, the memory seemed to have more life in it and eventually settled down at 318 MHz. Anything higher and the system would occasionally drop back to desktop while running 3D applications. Still.... 318MHz!

For testing purposes we're going to make an exception to our standard of running overclocking tests with low latencies, and run the OCZ PC4800 DC Platinum LTD Ed overclocking benchmarks at 318 MHz with lax timings.

pcstats test system specs: processor: amd athlon64 4000+ clock speed: 12 x 200 mhz = 2.4 ghz 8 x 316 mhz = 2.52 ghz motherboards: dfi lanparty nf4 sli-dr (nf4-sli) videocard: msi rx800xt-vtd256e memory: 2x 512mb corsair twinx3200xl pro 2x 512mb centon gemini pc3200 2x 512mb ocz pc4000 gold dc vx 2x 512mb ocz pc4800 platinum dc ltd ed hard drive: 74gb western digital raptor cdrom: gigabyte go-w0808a dvd burner powersupply: pc power & cooling turbocool 510 sli heatsink: prometeia mach ii gt (review) Software Setup WindowsXP Forceware NF4 6.53 Catalyst 5.4 Benchmarks Business Winstone 2004 SiSoft Sandra 2005 PCMark04 3DMark2001SE 3DMark05 X2: The Threat UT2003 UT2004 Doom 3

Note: We could not get the 7.5x multiplier working for this test, every time it was selected the system would not boot.

PCSTATS Test Methodology