Intel Core Duo (Yonah) Performance Preview - Part II
by Anand Lal Shimpi on December 19, 2005 12:55 PM EST- Posted in
- CPUs
At the end of November, we finally did what we had been waiting to do for so long - provide the first performance benchmarks of Intel's Yonah processor, the dual core successor to the highly acclaimed Pentium M. However, our initial performance investigation was not without its flaws. Given the short amount of time that we had for benchmarking, we were forced to compare to older numbers from previous reviews, which unfortunately lacked updated gaming, encoding and 3D rendering tests.
Despite the shortcomings of the initial article, we did manage to get a good look at the performance that we could expect from Yonah. Mainly, it was a fairly strong successor to the single core Pentium M and even more impressive was that it offered performance equal to that of AMD's Athlon 64 X2 without an on-die memory controller. Many AnandTech readers kept our methods in check, however, by quickly pointing out that the Yonah vs. Athlon 64 X2 comparison wasn't exactly fair, as Yonah is equipped with a full 2MB of L2 cache, whereas the Athlon 64 X2 3800+ that we were comparing it against only had 512KB per processor, possibly painting Yonah in a better light.
So for this follow-up, we've done two important things. For starters, we've updated the benchmark suite considerably, including modern day games and a few professional-level applications hopefully to get a better perspective on Yonah's performance. We've also included an Athlon 64 X2 running at 2.0GHz, but with each core having a full 1MB L2 cache, making the Yonah vs. X2 comparison as close to even as possible (not mentioning the fact that AMD has twice the advantage in this round, with both a larger L1 cache and an on-die memory controller, but it should make things interesting).
We won't be revisiting the issue of power consumption, as we already did that at the end of our last article, but needless to say, Yonah is the most efficient dual core processor that we've tested to date. Granted that it does have the advantage of being on Intel's 65nm process whereas the Athlon 64 X2 is still based on AMD's 90nm process, but given that AMD is around a year away from transitioning to 65nm, it is an advantage that Intel has the right to enjoy.
Despite the shortcomings of the initial article, we did manage to get a good look at the performance that we could expect from Yonah. Mainly, it was a fairly strong successor to the single core Pentium M and even more impressive was that it offered performance equal to that of AMD's Athlon 64 X2 without an on-die memory controller. Many AnandTech readers kept our methods in check, however, by quickly pointing out that the Yonah vs. Athlon 64 X2 comparison wasn't exactly fair, as Yonah is equipped with a full 2MB of L2 cache, whereas the Athlon 64 X2 3800+ that we were comparing it against only had 512KB per processor, possibly painting Yonah in a better light.
So for this follow-up, we've done two important things. For starters, we've updated the benchmark suite considerably, including modern day games and a few professional-level applications hopefully to get a better perspective on Yonah's performance. We've also included an Athlon 64 X2 running at 2.0GHz, but with each core having a full 1MB L2 cache, making the Yonah vs. X2 comparison as close to even as possible (not mentioning the fact that AMD has twice the advantage in this round, with both a larger L1 cache and an on-die memory controller, but it should make things interesting).
We won't be revisiting the issue of power consumption, as we already did that at the end of our last article, but needless to say, Yonah is the most efficient dual core processor that we've tested to date. Granted that it does have the advantage of being on Intel's 65nm process whereas the Athlon 64 X2 is still based on AMD's 90nm process, but given that AMD is around a year away from transitioning to 65nm, it is an advantage that Intel has the right to enjoy.
Facebook
Twitter
RSS
103 Comments
View All Comments
Furen - Monday, December 19, 2005 - link
The P6 has two FP units: An FADD unit and an FMUL unit. One of the big weaknesses of the P6 is the fact that the FMUL unit is not fully-pipelined but instead uses part of the FADD unit for FMUL operations. The K7, on the other hand, has three fully-pipelined units, an FADD, an FMUL and an FSTORE.tayhimself - Monday, December 19, 2005 - link
No he's not. AT's hardware reviewers are nublets. One thing to note though, Dothan FPU is better than the P4's hence its gaming performance advantage over the P4 in the old tests that everyone saw. It's likely that Yonah FPU is still the same as Dothan (similar to P3) and inferior to AMD's.saratoga - Monday, December 19, 2005 - link
Actually the FPU on the P4 was tremendously more powerful then Dothan or Yonah. While games do use the FPU, they're not that bottlenecked by it on modern systems. The reason Dothan did so well was because of its large, very low latency L2 cache. This is roughly equivilent to the primary advantage of the K8, a very low latency memory controller.tayhimself - Monday, December 19, 2005 - link
Youre right about the low latency L1/L2 caches on the Dothan, but the P4 (Williamette/Northwood) has those as well. But the P4 FPU is only powerful in SSE2 mode where it can load store larger chunks of data. Not all games use that unfortunately.saratoga - Monday, December 19, 2005 - link
You're wrong on several points.First:
Dothan L2 latency (clks): 10 clks
Northwood L2 latency (clks): 18 clks (approximately)
So Dothan's L2 cache is roughly 2x as fast and 4x as large. If you compare prescott with its amazingly slow L2, the situation is even more biased towards Dothan. Clearly, in terms of cache performance Dothan has a massive advantage, at least once you're out of the L1.
Second, you're confusing SSE2 and vector processing. While SSE2 can perform vector ops, it also handles plan scaler as well. In x86-64 SSE actually replaces the traditional x87 unit. The relative performance of the two is irrelevent however, the P4 was faster in both.
coldpower27 - Monday, December 19, 2005 - link
Dothan I agree with as having 10 Cycle Cache.
Northwood has 16 Cycle Cache.
Well you also got to keep in mind northwoods clock frequency plays a role in speeding up the cache, accces latencies for Dothan @ 2.0GHZ vs Northwood @ 3.2GHZ are basically equivalent. Though the 2.26GHZ Dothan has the fastest cache of all.
AlexWade - Monday, December 19, 2005 - link
Although, "Core Duo" is a stupid name. Why does Intel have to be so different? "Core Duo" is a little confusing. Is Duo a code name? What?However, despite the stupid name, we've really turned a corner in performance. Intel can make a good CPU when they realized speed isn't the future. Looks like I should start considering replacing my old Pentium-M IBM T40p with the awesome battery life.
AMD needs to respond in kind with a great new CPU. The future looks bright. Competition is once again is good for everyone.
LuxFestinus - Tuesday, December 20, 2005 - link
The ambiguously gay duo, with Ace and Gary.:) An old SNL skit.ksherman - Monday, December 19, 2005 - link
Personally, i dont like that AMD is just sitting back, seemingly waiting for Intel to catch up... They need to kick Intel while their down. these new Processors from intel look really nice and i am likely to buy one, but in a mactel laptop. I am happy for INtel that they are catching up, but AMD really NEEDS to step up and do soemthing new.Calin - Tuesday, December 20, 2005 - link
AMD's income is lower than Intel uses for R&D. You really can't expect from AMD to develop something faster than Intel can.For AMD, to have an processor they could improve a step at a time since the introduction of the Athlon64/Opteron was a need - Intel is able to mantain several teams for microprocessor development, but AMD only has money for one. And AMD will milk the market for as much as possible, selling processors that are easy to make for prices that market will accept. If AMD will start selling a higher processor grade, they would need to reduce the price for lower speed processors. This is why the 2800+ and 3000+ are discontinued - they would have to sell them too cheap.