We have tested these modules in a slightly different way to how we used to test modules on a Pentium 4 system, in that we have tried to keep the CPU speed fairly linear so that we can highlight the differences between, say, 200MHz front side bus and 300MHz front side bus, with the memory running synchronous.
AMD Athlon 64 FX-55; DFI LANPARTY nF4 SLI-DR (NVIDIA NForce4 SLI); BFGTech GeForce 6600 GT OC; Western Digital 200GB Caviar SATA 150 Hard disk drive; OCZ PowerStream 520W Power Supply; Windows XP Professional Service Pack 2; DirectX 9.0c; NVIDIA NForce4 Standalone chipset drivers, version 6.53; NVIDIA Forceware display drivers, version 71.89.
- OCZ PC5000 EL Platinum (DFI nF4 Special);
- OCZ PC3500 EB Platinum;
- Corsair TwinX1024-3200XL.
We went through several BIOS revisions on the motherboard, in order to try and find one that worked best for all modules. However, we had problems with the newer beta BIOS revisions that have been posted on DFI-Street
, so we were left running the latest official BIOS, dated 10/03/2005. In general, this BIOS is not too bad, but we had some slight issues with both our Corsair TwinX modules and the OCZ Enhanced Bandwidth series.
The Corsair TwinX did not seem to want to play ball at anything other than CAS2.0, while the OCZ EB modules seemed to underperform when running in 1:1. We have had the modules running at 250MHz using the 3:2 memory divider when we found that the nF4 SLI-DR was 24 hours Prime95 stable at 375MHz HTT. Unfortunately, they did not seem to want to show any kind of stability above 245MHz FSB today. As a result of these little niggles, we have included results for the Corsair at it's 'best-stock' timings, as we found that CAS2.0 stability topped out at 225MHz in Prime95, no matter how loose we set the remaining memory timings.
During our testing, we found that the tRAS (the large value amongst the memory timings) delivered the best bandwidth at a value of 10 on the Samsung-based modules, while the OCZ Enhanced Bandwidth series was most efficient with a tRAS of 9.
Interestingly, Corsair's 3200 XL was not as fast as the OCZ PC5000 at 200MHz (400MHz DDR). We suspect that this is down to the fact that the OCZ PC5000 EL Platinum Series memory on test here is fine tuned for the DFI nF4 series motherboards, and thus performs slightly better at the same clock speed. Corsair's PC3200 XL were deserved winners of our excellence award a long while back, and we still feel that they're great memory modules for anyone looking for great bandwidth across a wide range of platforms.
We feel that the issues we came across when overclocking the Corsair memory was down to BIOS related problems, rather than poor memory modules. We tried a newer beta BIOS, which did seem to help the problem of moving away from CAS2.0, but we encountered some problems with system stability on that BIOS, even at 200MHz FSB, across all memory modules that were tested.
Looking back at our experiences with OCZ's PC5000 EL Platinum Series memory modules, we found that we were unable to reach the rated 313MHz with our processor, memory and motherboard combination. However, we do not believe that the memory, or motherboard for that matter, was the problem. Our processor is based on the Clawhammer core, which has an older memory controller.
We believe that the memory controller on our Athlon 64 FX-55 is limiting our overclocking experiences with this memory, because there is plenty more left in the tank for the OCZ PC5000. We were able to get 310MHz FSB close to stable in memtest, failing once every two full loops at 2.5-4-3-10 with only 2.9v. Increasing the voltage above 2.9v did not help matters much, as is typical with most Samsung TCCD memory modules.
On the whole, we feel that OCZ's PC5000 EL Platinum Series are very versatile in their use. Whether it be at 200MHz FSB, where they were capable of running at some of the tightest timings possible of 2.0-2-2-10. Or at over 300MHz FSB, where they were capable of holding good timings delivering some great unbuffered memory bandwidth.
The price of the modules is set to be around £200-£220 in the UK when they land, and $300 in the USA. There are no stores in the UK that stock them right now, but Gladiator Computers
are set to be one of the first to receive stock. They are expecting their stock to arrive in about two weeks time, and should be priced at £209.00 inc. VAT for the 1GB kit providing the exchange rate does not change dramatically in the next couple of weeks.
Corsair's PC3200 XL is very good value at £135 on Scan
, but the question you have to ask yourself is whether you are planning to overclock your CPU past 250MHz FSB - that is where Corsair's PC3200 XL typically tops out. There is of course Corsair's PC4400 C25 modules
, which are very competitively priced, but not quite as versatile as these OCZ modules. They're tweaked to run on the DFI nF4 series, and thus they should gain higher speeds, and performance, than most competing modules. That's certainly what we've found to be the case here.
Unfortunately, due to the price, they're modules that only the serious enthusiast who is looking for unparalleled performance at over 300MHz FSB is likely to consider. Everyone else should look for something with significantly better value.