Heat has always been one of the largest limiting factors in PC enthusiasts quest for the ultimate overclock. Components such as CPU's, Graphics Cards and Memory all produce increased levels of heat when using extra voltage to push components to their limits. Until recently, one of the most common ways to disperse this heat was using a heatsink and fan, or in the case of memory modules - a heatspreader.
The heatspreader has been used on memory modules for several years, but has always been subject to criticism by many enthusiasts who believe that their design does more harm than good, trapping heat rather than dispersing it. There is certainly a level of truth in this statement, as many heatspreaders use low conductivity materials and have flat surface areas - all of which hinder the convection of heat into the surrounding air.
One of the more recent methods of removing heat from computer components is using heatpipes. This method uses pipes filled with a small quantity of liquid that evaporates when heated, taking the heat away from the surface. Once the vapor has cooled, it returns to a liquid, falls back down to the heat source and can begin the whole process again. This method has proven to be extremely effective and has recently been used in many award winning CPU heatsinks. For this reason it's no surprise that OCZ, one of the greatest innovators in the DDR memory market has used this very cooling method on their latest Reaper HPC DDR2 modules.
The following information has been taken directly from OCZ's website:
The Reaper HPC is an innovative cooling solution developed by OCZ to effectively minimize heat produced by high-speed memory. As heat rises into the thermo-conductive copper heat pipe conduit, it is dissipated through the strategically-placed compact aluminum fin array. By guiding performance-robbing heat away from key memory components, the unique Reaper HPC design helps facilitate improved overclocking performance, while improving longevity and stability of the modules.
The first modules to be incorporated with the new Reaper heatsink are rated at 1066MHz and run at CL 5-5-5. Featuring an EPP (Enhanced Performance Profiles) programmed SPD, PC2-8500 Reaper HPC modules will immediately boot at the rated specs on the latest generation of NVIDIA® SLI™ chipsets. Although the OCZ Reaper HPC series was coined for enthusiasts, EPP eliminates the need for manual configuration and makes memory optimizations a household item for the complete range of consumers looking to maximize system performance through overclocking.
As part of OCZ’s line-up of premium memory, PC2-8500 modules are backed by a Lifetime Warranty and industry-leading technical support.
Special Features • Reaper HPC Heatsink* • EPP-Ready 2.35V EVP**
* The Reaper HPC series uses heat pipe technology to rapidly remove heat from the main body of the memory modules and conduct the thermal load to the extended radiator fin array. The addition of the extended fin array nearly doubles the total surface area available for heat dissipation while the heat pipes warrant near isothermicity throughout the entire design. The result is a doubling in effective heat dissipation at equal delta t or, in real systems, a significantly lower operating temperature of the memory modules.
**OCZ EVP (Extended Voltage Protection) is a feature that allows performance enthusiasts to use a VDIMM of 2.35V without invalidating their OCZ Lifetime Warranty.
OCZ have always catered for the overclocking community, and it's great to see that there's been no change of ethics in their latest Reaper series. All Reaper modules come complete with a lifetime warranty that covers overclocking and running the modules at up to 2.35v.
Interestingly, the stock voltage (2.3v) for the Reaper kit is a tad higher than most other PC2-8500 kits we've reviewed recently. This could pose problems for people with non-enthusiast motherboards that may be unable to provide this kind of voltage to the memory slots. If you are planning on purchasing a Reaper kit, it would certainly be worth checking in your motherboard manual for available voltage options first.
Overclockers will be delighted to hear that the Reaper modules are based around the highly favorable Micron D9 (D9GMH) IC's. These have performed very well in previous reviews, and I'm sure the heatpipe cooling will help us push them to their limits later on in the review.
The clear plastic blister pack style packaging seems to be a favourite with memory manufacturers. For this reason I certainly wasn't surprised to see OCZ Reaper modules using the same packaging as previously seen on their Titanium kit that we reviewed a short while ago. It would have been nice to see the Reaper kit in some kind of special edition box considering they are not your average modules, but this would have obviously added unnecessary extra cost to their overal price.
Contained within the blister pack is a card insert printed with firey yellow background. While the front of the insert is purely for cosmetic reasons, the back offers basic information on the Reaper modules and a diagram of how the HPC (Heat Pipe Conduit) technology works.
When we first received news of the OCZ Reaper modules back in February, their unique design was met with a mixed response. Some praised them for their unique heatpipe design, while others questioned it's effectiveness compared to the finned heatsink design found on OCZ's highly awarded FlexXLC modules. The closest product that they could be compared to at the time was Thermalright's HR-07 aftermarket heatspreader. These featured a half-loop heatpipe, requiring them to be installed a certain way up in order for them to work correctly. Thankfully this isn't a problem for the Reaper modules, as their full-loop heatpipe design allows them to be installed at almost any angle.
When I first saw an image of these modules in OCZ's press release I must admit thinking they looked slightly 'tacky'. This would have been very uncharacteristic of OCZ who's name is often synonymous with high quality, and trusted by millions of PC enthusiasts around the world. Thankfully the press release images didn't do the modules justice....
The OCZ Reaper HPC kit features grooved aluminium heatspreaders which are firmly affixed to the modules with adhesive tape and two screws. Both the heatpipe fin array and the heatpipes themselves are extremely sturdy and do not shift position if you attempt to shake them.
Processor: Intel Core2Duo E6700 "Conroe" Motherboard: Asus Commando P965 (unmodded) Graphics Card: BFG 8800GTS Overclocked (550mhz / 1600mhz) Hard Disks: 2x Hitachi Deskstar 80gb SATA-II 8mb Cache (RAID0) Power Supply: Enermax Infiniti 720w Operating System: Windows XP SP2
As with all DDR2 reviews on Overclock3D the Reaper modules were subjected to a series of benchmark tests under several different configurations. The configurations used tested the memory's ability to run at high frequencies, tight timings and also ensured that that it could run with 100% stability at stock settings.
Stock - DDR2-1066 / 5-5-5-15 / 2.3v
It's an unfortunate fact that some memory modules we've tested here at Overclock3D in the past haven't been able to run at their rated settings. For this reason, the first test we perform on any modules passing through the OC3D labs is their ability to run at the manufacturers stated timings, frequency and voltage.
I'm pleased to say that the OCZ Reaper modules passed this first test without any problems, managing the full DDR2-1066 (PC2-8500) at 5-5-5-15 with 2.3v.
Lowest Latency - DDR2-1066 / 5-4-4-8 / 2.35v
Having confirmed earlier in the review that the Reaper modules are based around Micron D9 IC's, I started by tightening the timings down to 4-5-5-10. This setting should have been easily achievable for modules of this type, but unfortunately they didn't want to play ball. With the voltage set to 2.35v the PC would blue screen on Windows startup at any CAS4 latency setting. After several hours of tweaking, the tightest achievable latency for this particular Reaper kit was 5-4-4-8.
Highest Frequency - DDR2-1156 / 5-5-5-15 / 2.35v
Despite the slightly disappointing latency overclock results, I set about finding the maximum frequency of the Reaper kit. With the voltage set to 2.35v the furthest the modules could be overclocked while still maintaining stability was 578mhz (DDR2-1156). This may not be the best overclock we've ever seen on an PC2-8500 kit here at OC3D, but an 8% overclock is certainly not to be sniffed at.
For the benchmark phase of our review, the OCZ Reaper HPC PC2-8500 2Gb kit was subjected to several popular benchmarks in order to illustrate outright performance. All benchmarks were run three times and an average taken to guarantee uniformity of the results.
Despite not being able to tighten the latency of the Reaper modules down to CAS4, running the modules at 5-4-4-8 still managed to provide a decent performance boost over the stock 5-5-5-15 timings in both Sisoft Sandra and Everest. As expected, the greatest performance boost was seen when running the modules at DDR2-1156, with an increase of ~10% being shown in all bandwidth results.
SuperPI tends to rely heavily on CPU performance and bandwidth for obtaining the best results. This can certainly be verified in the graphs above, with the DDR2-1156 results shaving several seconds off of the stock 5-5-5-15 and 5-4-4-8 PI times.
Tighter memory latencies didn't really seem to have much effect on either of the 3DMark suites, with only a negligible amount of points between each of the 533mhz benchmarks. Yet again we can see that the higher frequency DDR2-1156 setting stole the show, even breaking 10000 points in 3DMark06.
The same pattern could also be seen in both Counter-Strike:Source and F.E.A.R benchmarks, with little (or no) difference being exhibited when running at the tighter 5-4-4-8 timings. However, the higher frequency DDR2-1156 results gave a healthy 19fps increase in CS:Source, showing that the game is very much CPU and bandwidth reliant.
OCZ Reaper HPC PC2-8500 2GB DDR2 Kit Page: 5
There's no question in my mind that the heatpipe design of the Reaper modules is more than just a gimmick. Throughout the review the aluminum heatspreader part of the modules remained cool, with the fin array radiating most of the heat into the surrounding environment. Unfortunately this didn't seem to help our in our efforts to break any previous review records with this kit, managing a middling DDR2-1156 overclock and timings of 5-4-4-8. I would have expected better from modules based on Micron D9 IC's, but as always overclocking is just pot luck and there's every chance that another Reaper kit could perform much better.
Retailing for around £145, the modules are certainly priced extremely competitively when compared with some other PC2-8500 kits we've reviewed recently. In addition to this, the lifetime guarantee, warranty up to 2.35v and effective heatspreader design certainly certainly adds extra value and features not see on kits from other manufacturers.
Pro's • Innovative heatpipe cooling (effectively moves heat away from the modules). • Excellent looks and build quality. • Reasonable overclock to DDR2-1156. • Great value for money.
Con's • Our sample kit didn't seem to respond very well to tight timings.
A special thanks to OCZ for providing this kit for review. Discuss this review in our forums.