Intel’s Core i7-975 & 950: Preparing for Lynnfield
by Anand Lal Shimpi on June 3, 2009 12:00 AM EST- Posted in
- CPUs
The Fastest Processor for Single Threaded Tasks
In the past we’ve had to make concessions for single-threaded application performance on modern day quad-core processors. For example, $266 will buy you two 3.33GHz cores or four 2.83GHz cores from Intel. I generally recommend going the quad-core option but there’s no getting around the fact that you do give up some performance when an application can’t take advantage of more than two threads.
With the Core i7 Extreme 975 the CPU can run at up to 3.60GHz when only one core is active (3.46GHz if more than one core is active). In my testing I found that the CPU almost always ran at its maximum turbo frequencies.
The graph below shows single-threaded performance in Cinebench R10. Note that while the Core 2 Duo E8600 (3.33GHz) was the top performer in this test for quite some time, the Core i7’s Turbo Mode has ensured that it’s no longer true.
The fastest single-threaded processors are now Intel's quad-core, eight-thread Core i7s
The biggest issue I see with the i7’s Turbo Mode today is that you only get one speed bin improvement (+133MHz) if 2 or more cores are active. The biggest boost (+266MHz) only comes when only a single core is active. Perhaps we’ll have to wait for Lynnfield for that.
The Test
Motherboard: | Intel DX58SO (Intel X58) Intel DX48BT2 (Intel X48) MSI DKA790GX Platinum (AMD 790GX) Gigabyte GA-MA790GP-DS4H (AMD 790GX) Gigabyte GA-MA790FX-UD5P (AMD 790FX) |
Chipset: | Intel X48 Intel X58 AMD 790GX AMD 790FX |
Chipset Drivers: | Intel 9.1.1.1010 (Intel) AMD Catalyst 8.12 |
Hard Disk: | Intel X25-M SSD (80GB) |
Memory: | G.Skill DDR2-800 2 x 2GB (4-4-4-12) G.Skill DDR2-1066 2 x 2GB (5-5-5-15) Qimonda DDR3-1066 4 x 1GB (7-7-7-20) Corsair DDR3-1333 4 x 1GB (7-7-7-20) |
Video Card: | eVGA GeForce GTX 280 |
Video Drivers: | NVIDIA ForceWare 180.43 (Vista64) NVIDIA ForceWare 178.24 (Vista32) |
Desktop Resolution: | 1920 x 1200 |
OS: | Windows Vista Ultimate 32-bit (for SYSMark) Windows Vista Ultimate 64-bit |
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strikeback03 - Thursday, June 4, 2009 - link
It was never able to properly shut the system down, the jumper configuration was set to hibernate the system 5 seconds after the ignition was turned off, instead it waited about a minute. Once a week or so it would refuse to start the system when the ignition was turned on until I pulled the computer case out of the dashboard and then put it back in. Eventually that problem grew more frequent, now when power is applied the led on the M3 blinks but it won't turn a system on. I replaced it with an M2-ATX and that has not had any problems. I have an Intel Atom 330 LF2 board, that board seems to draw the majority of its power off the 5V rail, so apparently the 6A the M3 could provide was not enough 5V for long-term use.TA152H - Wednesday, June 3, 2009 - link
Just an FYI, it's stated that the new i7 975 is 2.5 faster than Intel's fastest Pentium 4, but you didn't test Intel's fastest Pentium 4. The Pentium EE 965, running at 3.73 was it. It also had better power characteristics, since it was a later revision and, if I remember, correctly, had additional power savings modes enabled (EIST?).Also, you can't compare power draw between a 45 nm part and 65 nm and get disgusted. 45nm was a big advance for Intel in lowering power, and it would have been a very significant boost for the Pentium 4. Still, it was a terrible design, so your point is well taken, but it would not have been THAT terrible on 45nm. I think 5 GHz would have been easy, 6 GHz probably would not have been too difficult either. It's a pity we never got to see it, just out of curiousity.
aeternitas - Wednesday, June 3, 2009 - link
Curiousity? Take the average gain of all CPUs in question and you can come up with a rather accurate line of performance per Mhz. It would take longer to get the CPU performance numbers than to do the actual math.6 and 7GHz CPUs come with instability. Thats why we stopped at about 4Ghz and started to work smart instead of hard, like the G4/G5 cpus of old.
BabaBlackSheep - Wednesday, June 3, 2009 - link
I was just wondering how fast these stock fans for these processors are? The last time I got a new processor (Intel) was 3.5 years ago. It was insanely noisy. Has this changed?TotalLamer - Wednesday, June 3, 2009 - link
As much as I would love to support AMD, reviews like this make it very, very difficult at the moment.stimudent - Wednesday, June 3, 2009 - link
does this Intel processor have 'ethics violations' etched into the die too?TA152H - Wednesday, June 3, 2009 - link
Why? Neither processor is even remotely attractive to most people. They're performance is fine, but they are too expensive for what they are, again, for most people. If you're running a business, and faster performing processors helps your workers work faster, the $999 for the 975 is essentially nothing, and well worth it. But, for most people, neither of these processors are relevant.AMD makes horrible, badly-designed processors, but, is that so different from Intel IGPs? For a lot of people, and AMD processor with and 790GX is a better platform than an Intel based processor with the G45, and a lot of people only need an IGP.
I really do not think ATI was a bad purchase for AMD. It's made their platform a lot stronger vis-a-vis Intel. From a processor perspective, I agree, AMD sells trash, but as a platform, it can be very attractive because of ATI.
regnez - Wednesday, June 3, 2009 - link
No one said AMD processors were trash, except you. You kind of have a back and forth on your own argument: On the one hand, AMD cannot compete on the ultra high-end, on the other, not many people buy ultra high-end equipment.However, to say that AMD is releasing trash is just nonsense. Their lower-end processors are decent and compete with Intel reasonably well at given price points. They just don't have anything to match Intel at the top, which is not a big deal to most folks.
aeternitas - Wednesday, June 3, 2009 - link
"Most folks" do not read Anandtech. We need to look at the types that visit this site.I think that's a huge point.
Azsen - Wednesday, June 3, 2009 - link
When is Core i7 due on the notebook? I.e. quad core goodness?I wish Intel and AMD would focus on releasing better performing and lower power parts for the notebooks rather than desktops. Desktops are old school, the notebook is the way of the future and you can't notice much performance difference for general applications and even the odd game. Sure if you're a hard core gamer or need workstation performance you'd get a desktop as you can throw whatever you like in it, but everything else in between is better off as a notebook.