The Intel Xeon E7-8800 v3 Review: The POWER8 Killer?
by Johan De Gelas on May 8, 2015 8:00 AM EST- Posted in
- CPUs
- IT Computing
- Intel
- Xeon
- Haswell
- Enterprise
- server
- Enterprise CPUs
- POWER
- POWER8
POWER8 Servers: The Reality Check
As we've just seen, the specs of the POWER8 as announced at launch are very impressive. But what about the in the real world? The top models (10-12 at 4 GHz+, 2TB per socket) are still limited to the extremely expensive E870/E880, which typically costs around 3 times as much (or more) as a comparable Xeon E7 system. But there is light at the end of the tunnel: "PowerLinux" quad socket systems are more expensive than comparable x86 systems, but only by 10 to 30%.
The real competition for x86 must probably come from the third parties of the OpenPower Fondation. IBM sells them POWER8 chips at much more reasonable prices ($2k - $3k), so it is possible to build a reasonably priced POWER8 system. The POWER8 chips sold to third parties are somewhat "lighter" versions, but that is more an advantage than you would think. For example, by keeping the clockspeed a bit lower, the power consumption is lower (190W TDP). These chips also have only 4 (instead of 8) memory buffer chips, which "limits" them to 1 TB of memory, but again this saves quite a bit of power, between 50W and 80W. In other words, the POWER8 chips available to third parties are much more reasonable and even more competitive than the power gobbling, ultra expensive behemoths that got all the attention at launch.
Tyan already has an one socket server and several Taiwanese (Wistron) and Chinese vendors are developing 2 socket systems. Quad socket models are not yet on the horizon as far as we know, but is probably going to change soon.
POWER8 vs. Xeon E5 v3: SPECing It Out
Unfortunately we did not have access to a full blown POWER8 system at this time. But as our loyal readers know, we do not limit our server testing to the x86 world (see here and here) . So until a POWER8 system arrives, we'll have to check out the available industry standard benchmarks. To that end we looked up the SPEC CPU2006 numbers for a single socket CPU.
The 12 cores inside the POWER8 - the single socket chips found in the more reasonable priced servers - perform very well. The integer performance is only a few percentages lower than the Intel chip and POWER8's floating point performance is well ahead of the Xeon.
Overall the POWER8 is quite capable of keeping up with the Xeon E5-2699v3. And don't let the "2.3 GHz" official clockspeed fool you into thinking that the Xeons are clocked unnecessarily low, either: in SPECint, the XEON is running at 2.8 GHz most of the time.
Ultimately, the POWER8 is able to offer slightly higher raw performance than the Intel CPUs, however it just won't be able to do so at the same performance/watt. Meanwhile the reasonable pricing of the POWER8 chips should result in third party servers that are strongly competitive with the Xeon on a performance-per-dollar basis. Reasonably priced, well performing dual and quad socket Linux on Power servers should be possible very soon.
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TheSocket - Friday, May 8, 2015 - link
They sure wouldn't lose the x86-64 license since they own it and Intel is licensing it from AMD.melgross - Saturday, May 9, 2015 - link
But without the license from Intel, it is worthless. There's also the question of how that works. I believe that Intel doesn't need to license back the 64 bit extensions.Kevin G - Monday, May 11, 2015 - link
This one of the reasons why it would be in Intelsat best interest to let AMD be bought out with the 32 bit license intact. The 64 bit license/patents going to a third party that doesn't want to share would be a dooms day scenario for Intel. Legally it wouldn't affect anything currently on the market but it'd throw Intel's future roadmap into the trash.Death666Angel - Saturday, May 9, 2015 - link
Pretty sure some regulatory bodies would step in if Intel were the only x86 game in town. And x86-64 is AMD property.JumpingJack - Saturday, May 9, 2015 - link
Any patents on x86 are long expired, AMD only owns the IP related to the extension of the x86 not the instruction set.patrickjp93 - Monday, May 11, 2015 - link
Not true. The U.S. government has them locked up under special military-based protections. Absolutely no one can make and sell x86 without Intel's and the DOD's permission.Kevin G - Monday, May 11, 2015 - link
Got a source for that?I know that DoD did some validation on x86 many years ago. (The Pentium core used by Larrabee had the DoD changes incorporated.)
haplo602 - Friday, May 8, 2015 - link
hmm ... where's the RAS feature comparison/test ? did I miss it in the article ?TeXWiller - Friday, May 8, 2015 - link
In the E7v3 vs POWER comparison table, there should be 32 PCIe lanes instead 40 in the Xeon column.TeXWiller - Friday, May 8, 2015 - link
Additionally, it is the L3 in POWER8 that runs half of the core speed. L2 runs at the core speed.