With its Enhanced Bandwidth technology, OCZ Technology is looking to take memory module performance to its limits without needing the lowest possible CAS latency. In this review, we take a look at OCZ’s Enhanced Bandwidth 1 GB PC3200 Dual Channel Kit, and it does not disappoint!
Introduction
Most PC enthusiasts seem to want memory with the lowest CAS latency possible. This seems intuitive – the less clock cycles it takes to do something, the faster it can be done repeatedly. However, more factors than just CAS latency come into play when it comes to memory performance. That is why OCZ Technology developed their new Enhanced Bandwidth line of DDR memory modules. OCZ is shirking conventional wisdom when it comes to memory performance and CAS latency being king. Rather than try to explain it fully myself, I invite you to check out OCZ’s EB technology whitepaper. Basically, through extensive analysis, OCZ’s engineers determined that they can make their EB modules maintain higher effective bandwidth by focusing more on the precharge-to-active (tRP) and the RAS-to-CAS (tRCD) delays and by using the Variable Early Read Command feature available in DDR. The benefit of Variable Early Read Command is that it can nearly eliminate the penalty on performance a higher CAS latency can have during a sustained data transer. It accomplishes this by issuing a read command for an ongoing transfer a number of cycles early, with this number being equal to the current CAS latency.
OCZ wanted me to be clear about how I represent their Enhanced Bandwidth technology. The motivation for this product was presented to me by Andy Talamantez, an OCZ Product Consultant. The following paragraph from an e-mail he sent me sums it up well:
“As most every hardware enthusiast has become aware, Winbond has ceased production of their low-latency BH5, BH6 and CH5 RAM chips. The supply of the high yield chips is basically gone. OCZ set out to develop memory modules that are highly optimized through SPD, and will achieve nearly the same bandwidth results as the Winbond CAS_2 parts. Our stance is not that the CAS_2.5 Enhanced Bandwidth modules are “superior” to the Winbond modules that we have produced. The “EB” modules are competitive and will actually overclock to higher speeds than were allowed by the Winbond at CAS_2, while running reasonable voltages. Try and think of the EB modules as a competitive, cost effective replacement for an excellent and nearly unavailable product.”
For this review, I have paired OCZ’s one gigabyte dual channel kit of Enhanced Bandwidth PC3200 memory with an Atlon 64 system based on the K8T800 chipset. With its integrated memory controller, the Athlon 64 offers better memory performance than other mainstream Athlon CPUs. That is why using this system will help us test the upper performance limits of this memory. If OCZ’s claims hold true, we should be able to see performance on par with other memory with CAS latency set to two.
Specifications & Features
Specifications:
- Part Number: OCZ4001024EBDCPE-K
- Package: 1 GB (2 x 512 MB) Dual Channel Kit
- Latency: 2.5-3-2-8 (SPD Timings: 2.5-3-2-7) (CL-tRCD-tRP-tRAS)
- Voltage: 2.6 V
- Heat Spreader: Mirrored Platinum Copper
- Speed: DDR 400 MHz (PC3200)
- Type: 184-pin DDR SDRAM DIMM
- Error Checking: Non-ECC
- Registered/Unbuffered: Unbuffered
- Warranty: Lifetime
I am glad to see that the rated timings are the same as the SPD settings with only one exception – active-to-precharge (tRAS) delay. The tRAS SPD value is actually lower than what OCZ has on its website.
Performance
As I mentioned above, I decided to test the performance of OCZ’s PC3200 Enhanced Bandwidth memory kit with an Athlon 64 system. You can check out the specs below. I was able to overclock the memory to 430MHz DDR, which is not a groundbreaking overclock, but it is decent and gives a nice little boost in performance. Unfortunately, this system’s BIOS does not allow for tweaking memory timings, so I could not check if these modules were capable of running at a lower CAS latency.
A representative from OCZ told me that he believed first generation Athlon 64 chipsets overclock better with only one DIMM slot populated, so I decided to test that theory with a couple more benchmark runs. Interestingly, I achieved better stock speed and overclocking results with only one DIMM. I was able to hit 440 MHz with one DIMM and increasing the DIMM voltage to 2.7 volts. Anything past that was very unstable.
For reference, I have included stock speed and memory timings results for another 1 GB memory kit, the Corsair TWINX1024-3200LLPRO. The SPD memory timings for these modules are 2-3-2-6.
Test System
- AMD Athlon 64 3200+
- Gigabyte GA-K8VNXP (BIOS version F4) (reviewed January 2004)
- Reference GeForce FX 5950 Ultra
- Hitachi Deskstar 7K250 80GB Serial ATA 7200RPM Hard Drive w/8MB Buffer
- Pioneer DVD-ROM
- Operation System: Windows XP (32-bit) with Service Pack 1
- Chipset Driver: 4.48
- Graphics Card Driver: Forceware 53.03
- DirectX Version: 9.0b
PCMark04 (version 1.0.0)
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SiSoftware Sandra (version 2004.10.9.89)
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Overall, the performance of this memory is about what I would expect for enthusiast PC3200 RAM. However, as you will see below, the performance actually improved a little bit when I used only one stick of RAM.
PCMark04 (version 1.0.0)
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SiSoftware Sandra (version 2004.10.9.89)
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Apparently, the OCZ representative was correct! I was able to hit 440 MHz with only one DIMM. What’s most remarkable about this is the huge jump in bandwidth between 430 and 440 MHz! There is nearly the same amount of an improvement in that 10 MHz increase in DDR clock speed as there was in the 30 MHz jump from 400 to 430 MHz. Maybe 440 MHz is the sweet spot for this memory. Most of the benchmark results at 440 MHz are the highest I’ve ever been able to achieve!
Conclusion
OCZ Technology has another great product in their lineup! It seems as if their Enhanced Bandwidth technology really begins to show its muscle at higher clock speeds, though. Perhaps that is why these modules simply perform on par with competing products at stock speeds. However, it is important to note that these “competing products” would be similar PC3200 modules running stable with CL=2, since that is probably what they would have to be running at to keep up with these modules. In other words, OCZ’s EB modules deliver a viable alternative to increasing performance by simply decreasing CAS latency.
I searched numerous major online retailers (from the list at ocztechnology.com), and the only one where I could find this new product was accessmicro.com. If you’re interested, a google search helped me find it at a couple other places. Accessmicro.com offered it for $331 as of April 17. From my other digging around, it looks like you will have to expect to pay at least $300 for this dual channel 1 gigabyte kit. That’s a pretty good price for enthusiast RAM that lives up to its billing.
Pros:
Cons:
For achieving great performance by “thinking outside the box,” OCZ deserves
a score of 9 out of 10 and the Bjorn3D Seal of Approval for their
1-GB Enhanced Bandwidth PC3200 Dual Channel Kit (OCZ4001024EBDCPE-K).