Conclusion
While DDR2 Memory does not exhibit the same bandwidth or performance on the AM2 and Conroe platforms, they do perform at the same timings and voltages when going from one platform to another. This was clearly demonstrated in benchmarking tests performed on AM2 and Conroe platforms. This means readers can examine test results performed on a Core 2 Duo test bed with XYZ memory, and reasonably expect that XYZ memory to perform at the same speeds and the same memory timings and voltages on an AM2 platform - provided those settings are available.
There are always the variations in chipset and BIOS that can cause problems with a memory on one brand/model of motherboard and no problems on another brand/model, but that is also true even if you are planning to use the DDR2 on the same type of platform. We have sometimes seen where a brand of memory runs very well on an MSI platform, for example, but where it would not run at all on a DFI platform using the same chipset and CPU. Those types of compatibility issues will always happen, but in general if a memory tests well on Conroe it should do just as well on AM2.
This fact will make our memory testing much simpler, and we plan to perform all upcoming memory testing on the currently more flexible Core 2 Duo test platform. AM2 buyers can expect similar results with the same DDR2 memory on their AM2 motherboards.
A few conclusions about AM2 performance compared to Core 2 Duo performance are also inescapable in looking at our test results. First, Intel has done a remarkable job of concealing the issue of not having an on-processor memory controller. The intelligent look-ahead for memory works very well, and it makes the chipset-based Core 2 Duo memory controller appear to be as fast as the on-processor AM2 in many cases. This does not change the fact that the AM2 memory bandwidth is really greater than Core 2 Duo or the fact that AM2 scales better in memory, exhibiting a steeper slope in performance increase as memory speed increases than does Core 2 Duo. That just means as Memory Speed increases AM2 will benefit more and Intel will eventually need to move to an on-processor controller.
Probably the hardest conclusion for many will be the fact that increasing memory speed, increasing clock speed, and increasing CPU speed alone will not be enough for AM2 to catch up to Core 2 Duo in performance. The performance gap that remains when overclocking AM2 to 2.93GHz at 266 clock speed with DDR2-1067 is still huge. A die-shrink from 90 to 65nm and the additional cache that will allow will definitely help, but we are even skeptical there with Core 2 Duo already overclocking to 4GHz and beyond. No doubt AMD will find a solution, but it is now clear this will not be an easy fix for AMD.
The deep price cuts announced by AMD yesterday will definitely help. The new numbers indicate AM2 will be very competitive at the low end to low-mid of the processor food chain - a spot they have held in the past and where they have still managed to survive. The low end looks very competitive, and AMD is positioned close enough to mid-range in performance to keep Intel honest. There is no mistaking, however, that Intel Core 2 Duo owns the mid to high-end of the current processor market.
With this memory analysis, the memory playing field is hopefully a lot clearer for those shopping for DDR2 memory. Our next memory articles will compare memory performance of DDR2 on the Core 2 Duo Memory Test Bed. This began with the 6 high-performance memories and the 7 value memories tested in the Conroe Buyers Guide. It will continue with evaluations of the fastest memories available from both Corsair and OCZ.
While DDR2 Memory does not exhibit the same bandwidth or performance on the AM2 and Conroe platforms, they do perform at the same timings and voltages when going from one platform to another. This was clearly demonstrated in benchmarking tests performed on AM2 and Conroe platforms. This means readers can examine test results performed on a Core 2 Duo test bed with XYZ memory, and reasonably expect that XYZ memory to perform at the same speeds and the same memory timings and voltages on an AM2 platform - provided those settings are available.
There are always the variations in chipset and BIOS that can cause problems with a memory on one brand/model of motherboard and no problems on another brand/model, but that is also true even if you are planning to use the DDR2 on the same type of platform. We have sometimes seen where a brand of memory runs very well on an MSI platform, for example, but where it would not run at all on a DFI platform using the same chipset and CPU. Those types of compatibility issues will always happen, but in general if a memory tests well on Conroe it should do just as well on AM2.
This fact will make our memory testing much simpler, and we plan to perform all upcoming memory testing on the currently more flexible Core 2 Duo test platform. AM2 buyers can expect similar results with the same DDR2 memory on their AM2 motherboards.
A few conclusions about AM2 performance compared to Core 2 Duo performance are also inescapable in looking at our test results. First, Intel has done a remarkable job of concealing the issue of not having an on-processor memory controller. The intelligent look-ahead for memory works very well, and it makes the chipset-based Core 2 Duo memory controller appear to be as fast as the on-processor AM2 in many cases. This does not change the fact that the AM2 memory bandwidth is really greater than Core 2 Duo or the fact that AM2 scales better in memory, exhibiting a steeper slope in performance increase as memory speed increases than does Core 2 Duo. That just means as Memory Speed increases AM2 will benefit more and Intel will eventually need to move to an on-processor controller.
Probably the hardest conclusion for many will be the fact that increasing memory speed, increasing clock speed, and increasing CPU speed alone will not be enough for AM2 to catch up to Core 2 Duo in performance. The performance gap that remains when overclocking AM2 to 2.93GHz at 266 clock speed with DDR2-1067 is still huge. A die-shrink from 90 to 65nm and the additional cache that will allow will definitely help, but we are even skeptical there with Core 2 Duo already overclocking to 4GHz and beyond. No doubt AMD will find a solution, but it is now clear this will not be an easy fix for AMD.
The deep price cuts announced by AMD yesterday will definitely help. The new numbers indicate AM2 will be very competitive at the low end to low-mid of the processor food chain - a spot they have held in the past and where they have still managed to survive. The low end looks very competitive, and AMD is positioned close enough to mid-range in performance to keep Intel honest. There is no mistaking, however, that Intel Core 2 Duo owns the mid to high-end of the current processor market.
With this memory analysis, the memory playing field is hopefully a lot clearer for those shopping for DDR2 memory. Our next memory articles will compare memory performance of DDR2 on the Core 2 Duo Memory Test Bed. This began with the 6 high-performance memories and the 7 value memories tested in the Conroe Buyers Guide. It will continue with evaluations of the fastest memories available from both Corsair and OCZ.
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Coogcheese - Tuesday, July 25, 2006 - link
Is the latency issue really due to intelligent look-ahead or the vast cache size difference between the two processors? I'd like to see a benchmark comparison between an 2MB cache opeteron and an equally cached/clocked/timed Conroe. That would settle some debate (yea, yea...wishful thinking).It could also help lend some insite to what AMD might do in the short & long term as a response as well.
The author of the review seems to give alot of credit to "look-ahead" but I found this benchmark comparison to be interesting: http://www.hexus.net/content/item.php?item=6256&am...">http://www.hexus.net/content/item.php?item=6256&am...
Opteron doesn't seem to have same problem that the Athlon does in terms of latency performance. Which could be why amd execs seem less than panicky at this point. It would allude to a market war similar to the megahurtz war that led to amd coming out with the model # system...this time it could be intel taking advantage of their capacity by laying the cache size smack down on amd instead of megahurtz.
If it is cache size and not "look-ahead" then amd could (could mind you...but would they? and how many could they?) respond much quicker I'd think. If its new technology or a combo of cache and new tech then amd will be in a much worse position imho.
Whatever the case its great for the consumer(me). Thank goodness for competition. Daddy needs a new pair of cores...and the price just got a whole lot better!
ChronoReverse - Tuesday, July 25, 2006 - link
It would indeed be very interesting to see a 2MB L2 1.6GHz Core 2 Duo E6200 compared against 2MB L2 1.6GHz Opteron 160.The shared L2 cache of the Conroe will give it a nice advantage though.
bob661 - Tuesday, July 25, 2006 - link
Anyonehave any speculation as to how much the initial Conroe's will cost? We pretty much know that the motherboards will be expensive but what about the CPU's?ChronoReverse - Tuesday, July 25, 2006 - link
The pricing has been out for a while already. They're relatively reasonable considering the performance. Only the Extreme Edition as usual is really expensive (but still not as expensive as I'd have thought).Too bad the motherboards are so expensive. I'm taking a look at that Asrock board, but I doubt it'll have any good overclocking capability.
Gary Key - Tuesday, July 25, 2006 - link
The less expensive boards for Conroe will fully hit the market near the end of August. ;-) We expect to see ECS, Foxconn, MSI, Epox, and others fully ramped up in a couple of weeks on the value boards. Until then, the Gigabyte DS3 is a really good board for overclocking the E6300/E6400 series and our Biostar and Abit boards continue to improve with each bios release. All three are under $145 now with others joining them shortly if the P965 is interesting to you. The ASRock board actually surprised us, but remember the VCore voltage cannot be adjusted. The $50~$100 market will be very interesting as the 945P, 946PL, and NV570SLI chipsets will dominate this section until the G965 boards start arriving in September if decent intergrated graphics are on your wish list, if not all of the boards will offer good performance for the money. The under $55 market will consist of VIA and SIS chipsets from PC-Chips and ASRock with a few majors like ECS and MSI having boards based on these chipsets.
Wesley Fink - Tuesday, July 25, 2006 - link
Everest Scores have been rerun with Version 3.01, which was released on July 16, 2006. Since the scores from the new version can not be compared to older Everest scores, we reran all the Everest benchmarks. 3.01 is said to provide full and complete support for Conroe and Merom. Values are different in that Memory WRITE and READ scores are reported as much higher than past Everest testing. Latency is also reported as closer between AM2 and Core 2 Duo with the 3.01 version of Everest. Charts and commentary have been revised using the new results.jjunos - Tuesday, July 25, 2006 - link
Thanks for the update wes! It always shows the quality of the website when they listen to their community and and willing to rerun all their tests in the sake of being correct! kudos!TonyB - Tuesday, July 25, 2006 - link
is it just me or did AMD just get pwned?bob661 - Tuesday, July 25, 2006 - link
I personally don't care about who owns who. I just want competition so I can get this stuff for cheap. I'm a best bang for the buck guy.goinginstyle - Tuesday, July 25, 2006 - link
Everyone benefits here with the performance improvements Intel has brought to the table and an AM2 3800+ at $150 is just an incredible value. Conroe made it easy for AMD users to upgrade their performance for very little money.