The Sandy Bridge Review: Intel Core i7-2600K, i5-2500K and Core i3-2100 Tested
by Anand Lal Shimpi on January 3, 2011 12:01 AM ESTPower Consumption
Power consumption is very low thanks to core power gating and Intel's 32nm process. Also, when the integrated GPU is not in use it is completely power gated as to not waste any power either. The end result is lower power consumption than virtually any other platform out there under load.
I also measured power at the ATX12V connector to give you an idea of what actual CPU power consumption is like (excluding the motherboard, PSU loss, etc...):
| Processor | Idle | Load (Cinebench R11.5) |
| Intel Core i7 2600K @ 4.4GHz | 5W | 111W |
| Intel Core i7 2600K (3.4GHz) | 5W | 86W |
| AMD Phenom II X4 975 BE (3.6GHz) | 14W | 96W |
| AMD Phenom II X6 1100T (3.3GHz) | 20W | 109W |
| Intel Core i5 661 (3.33GHz) | 4W | 33W |
| Intel Core i7 880 (3.06GHz) | 3W | 106W |
Idle power is a strength of Intel's as the cores are fully power gated when idle resulting in these great single digit power levels. Under load, there's actually not too much difference between an i7 2600K and a 3.6GHz Phenom II (only 10W). There's obviously a big difference in performance however (7.45 vs. 4.23 for the Phenom II in Cinebench R11.5), thus giving Intel better performance per watt. The fact that AMD is able to add two more cores at only a 13W load and 300MHz frequency penalty is pretty impressive as well.
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aviat72 - Tuesday, January 4, 2011 - link
Though SB will be great for some applications, there are still rough edges in terms of the overall platform. I think it will be best to wait for SNB-E or at least the Z68. SNB-E seems to be the best future-proofing bet.I also wonder how a part rated for 95W TDP was drawing 111W in the 4.4GHz OC (the Power Consumption Page). SB's power budget controller must be really smart to allow the higher performance without throttling down, assuming your cooling system can manage the thermals.
marraco - Tuesday, January 4, 2011 - link
I wish to know more about this Sandy Bridge "feature":http://www.theinquirer.net/inquirer/news/1934536/i...
PeterO - Tuesday, January 4, 2011 - link
Anand, Thanks for the great schooling and deep test results -- something surely representing an enormous amount of time to write, produce, and massage within Intel's bumped-forward official announcement date.Here's a crazy work-around question:
Can I have my Quick Synch cake and eat my Single-monitor-with-Discrete-Graphics-card too if I, say:
1). set my discrete card output to mirror Sandy Bridge's IGP display output;
2). and, (should something exist), add some kind of signal loopback adapter to the IGP port to spoof the presence of a monitor? A null modem, of sorts?
-- I have absolutely no mobo/video signaling background, so my idea may be laugh in my face funny to anybody who does but I figure it's worth a post, if only for your entertainment. :)
Hrel - Wednesday, January 5, 2011 - link
It makes me SO angry when Intel does stupid shit like disable HT on most of their CPU's even though the damn CPU already has it on it, they already paid for. It literally wouldn't cost them ANYTHING to turn HT on those CPU's yet the greedy bastards don't do it.Moizy - Wednesday, January 5, 2011 - link
The HD Graphics 3000 performance is pretty impressive, but won't be utilized by most. Most who utilize Intel desktop graphics will be using the HD Graphics 2000, which is okay, but I ran back to the AMD Brazos performance review to get some comparisons.In Modern Warfare 2, at 1024 x 768, the new Intel HD Graphics 2000 in the Core i3 2100 barely bests the E-350. Hmm--that's when it's coupled with a full-powered, hyper-threaded desktop compute core that would run circles around the compute side of the Brazos E-350, an 18w, ultra-thin chip.
This either makes Intel's graphics less impressive, or AMD's more impressive. For me, I'm more impressed with the graphics power in the 18w Brazos chip, and I'm very excited by what mainstream Llano desktop chips (65w - 95w) will bring, graphics-wise. Should be the perfect HTPC solution, all on the CPU (ahem, APU, I mean).
I'm very impressed with Intel's video transcoding, however. Makes CUDA seem...less impressive, like a bunch of whoop-la. Scary what Intel can do when it decides that it cares about doing it.
andywuwei - Wednesday, January 5, 2011 - link
not sure if anybody else noticed. CPU temp of the i5@3.2GHz is ~140 degrees. any idea why it is so high?SantaAna12 - Wednesday, January 5, 2011 - link
Did I miss the part where you tell of about the DRM built into this chip?Cb422 - Wednesday, January 5, 2011 - link
When will Sandy Bridge be available on Newegg or Amazon for me to purchase?DesktopMan - Thursday, January 6, 2011 - link
Very disappointed in the lack of vt-d and txt on k-variants. They are after all the high end products. I also find the fact that only the k-variants having the faster GPU very peculiar, as those are the CPUs most likely to be paired with a discrete GPU.RagingDragon - Thursday, January 6, 2011 - link
Agreed. I find the exclusion of VT-d particularly irritating: many of the overclockers and enthusiasts to whom the K chips are marketed also use virtualization. Though I don't expect many enthusiasts, if any, to miss TXT (it's more for locked down corporate systems, media appliances, game consoles, etc.).With the Z68 chipset coming in the indeterminate near future, the faster GPU on K chips would have made sense if the K chips came with every other feature enabled (i.e. if they were the "do eveything chips").
Also, I'd like to have the Sandy Bridge video encode/decode features separate from the GPU functionality - i.e. I'd like to choose between Intel and Nvidia/AMD video decode/encode when using a discrete GPU.