The Sandy Bridge Pentium Review: G850, G840, G620 & G620T Tested
by Anand Lal Shimpi on August 23, 2011 12:11 AM ESTIn 2006 Intel introduced its tick-tock cadence for microprocessor releases. Every year would see the release of a new family of microprocessors as either a tick or a tock. Ticks would keep architectures relatively unchanged and focus on transitions to smaller manufacturing technologies, while tocks would keep fab process the same and revamp architecture. Sandy Bridge was the most recent tock, and arguably the biggest one since Intel started down this road.
At a high level the Sandy Bridge CPU architecture looked unchanged from prior iterations. Intel still put forth a 4-issue machine with a similar number of execution resources to prior designs. Looking a bit closer revealed that Intel completely redesigned the out-of-order execution engine in Sandy Bridge, while heavily modifying its front end. Sandy Bridge also introduced Intel's high performance ring bus, allowing access to L3 by all of the cores as well as Intel's new on-die GPU.
The Sandy Bridge GPU was particularly surprising. While it pales in comparison to the performance of the GPU in AMD's Llano, it does represent the first substantial effort by Intel in the GPU space. Alongside the integrated GPU was Intel's first hardware video transcoding engine: Quick Sync. In our initial review we found that Quick Sync was the best way to quickly transcode videos, beating out both AMD and NVIDIA GPU based implementations in our tests. Quick Sync adoption has been limited at best, which is unfortunate given how well the feature performed in our tests.
Sandy Bridge wasn't all rosy however. It was the first architecture that Intel shipped with overclocking disabled on certain parts. Any CPU without Turbo Boost enabled is effectively unoverclockable. Intel killed the low end overclocking market with Sandy Bridge.
The overclocking limits were a shame as Sandy Bridge spanned a wide range of price points. The low end Core i3-2100 was listed at $117 while the highest end Core i7-2600K came in at $317. While you can't claim that Sandy Bridge was overpriced at the high end, there's always room for improvement.
Despite abandoning Pentium as a high end brand with the 2006 release of Intel's Core 2 Duo, Intel has kept the label around for use on its value mainstream parts. Last year we saw only two Pentium branded Clarkdale parts: the G6950 and G6960. This year, powered by Sandy Bridge, the Pentium brand is a bit more active.
| Processor | Core Clock | Cores / Threads | L3 Cache | Max Turbo | Max Overclock Multiplier | TDP | Price |
| Intel Core i7 2600K | 3.4GHz | 4 / 8 | 8MB | 3.8GHz | 57x | 95W | $317 |
| Intel Core i7 2600 | 3.4GHz | 4 / 8 | 8MB | 3.8GHz | 42x | 95W | $294 |
| Intel Core i5 2500K | 3.3GHz | 4 / 4 | 6MB | 3.7GHz | 57x | 95W | $216 |
| Intel Core i5 2500 | 3.3GHz | 4 / 4 | 6MB | 3.7GHz | 41x | 95W | $205 |
| Intel Core i5 2400 | 3.1GHz | 4 / 4 | 6MB | 3.4GHz | 38x | 95W | $184 |
| Intel Core i5 2300 | 2.8GHz | 4 / 4 | 6MB | 3.1GHz | 34x | 95W | $177 |
| Intel Core i3 2120 | 3.3GHz | 2 / 4 | 3MB | N/A | N/A | 65W | $138 |
| Intel Core i3 2100 | 2.93GHz | 2 / 4 | 3MB | N/A | N/A | 65W | $117 |
| Intel Pentium G850 | 2.9GHz | 2 / 2 | 3MB | N/A | N/A | 65W | $86 |
| Intel Pentium G840 | 2.8GHz | 2 / 2 | 3MB | N/A | N/A | 65W | $75 |
| Intel Pentium G620 | 2.6GHz | 2 / 2 | 3MB | N/A | N/A | 65W | $64 |
| Intel Pentium G620T | 2.2GHz | 2 / 2 | 3MB | N/A | N/A | 35W | $70 |
The new Sandy Bridge based Pentiums fall into two lines at present: the G800 and G600. All SNB Pentiums have two cores (HT disabled) with 256KB L2 per core and a 3MB L3 cache. CPU core turbo is disabled across the entire Pentium line. From a performance standpoint, other than missing hyper threading and lower clocks - the Sandy Bridge Pentiums are very similar to Intel's Core i3.
Intel continues to separate the low end from the high end by limiting supported instructions. None of the Pentiums support AES-NI or VT-d. Other than higher clock speeds the 800 series only adds official DDR3-1333 support. The 600 series only officially supports up to DDR3-1066.
All standard Pentiums carry a 65W TDP. The Pentium G620T runs at a meager 2.2GHz and manages a 35W TDP. Regardless of thermal rating, the boxed SNB Pentiums come with an ultra low profile cooler:
These Pentium CPUs work in the same 6-series LGA-1155 motherboards as their Core i3/5/7 counterparts. The same rules apply here as well. If you want video out from the on-die GPU you need either an H-series or a Z-series chipset.
The Pentium GPU
When Intel moved its integrated graphics on-package with Clarkdale it dropped the GMA moniker and started calling it HD Graphics. When it introduced the Sandy Bridge Core i3/5/7, Intel added the 2000 and 3000 suffixes to the HD Graphics brand. With the Sandy Bridge Pentium, Intel has gone back to calling its on-die GPU "HD Graphics".
Despite the name, the Pentium's HD Graphics has nothing in common with Clarkdale's GPU. The GPU is still on-die and it features the same architecture as Intel's HD Graphics 2000 (6 EUs). Performance should be pretty similar as it even shares the same clock speeds as the HD 2000 (850MHz base, 1.1GHz turbo for most models). I ran a quick test to confirm that what Intel is selling as HD Graphics is really no different than the HD Graphics 2000 in 3D performance:
All is well in the world.
Where the vanilla HD Graphics loses is in video features: Quick Sync, InTru 3D (Blu-ray 3D), Intel Insider (DRM support for web streaming of high bitrate HD video) and Clear Video HD (GPU accelerated post processing) are all gone. Thankfully you do still get hardware H.264 video acceleration and fully audio bitstreaming support (including TrueHD/DTS-HD MA).
Missing Quick Sync is a major blow, although as I mentioned earlier I'm very disappointed in the poor support for the feature outside of the initial launch applications. The rest of the features vary in importance. To someone building a basic HTPC, a Sandy Bridge Pentium will do just fine. Personally I never play anything in 3D, never use the Clear Video HD features and never use Intel Insider so I wouldn't notice the difference between a Sandy Bridge Pentium and a Core i5 for video playback.
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yankeeDDL - Monday, September 5, 2011 - link
Averik, positive exchange of opinion and ideas is always nice, I think :)I wrote another comment a few pages down about comparing power consumption.
It is very difficult to compare power consumption based on the data above, however, a "quick and dirty" comparison can be done using the data from the graphs of the H264 decoding and the power under load.
You can see that the G620 uses 55% of the power of the X3, but the X3 takes 60% of the time to do the compression.
What this means is that under load, the G620 consumes less, but the X3 goes back idle much faster than the G620. Of course, this is one specific scenario: in general, it's clear that the G620 is more efficient, but also slower.
Considering the type of applications you indicate, I think the amount of time when the system will be at max power will be extremely low, compared to the idle time.
Unfortunately Anand did not compare the idle power consumption between these CPUs.
This page compares system level power consumption of both the X3 and the G620 (http://www.xbitlabs.com/articles/cpu/display/penti... and shows again the X3 on top. In the comment you see that with other MoBos the G620 idle power can be shaver a little and be made, at best, the same.
So I stand by my position: the G620 offers no advantage over the Athlon X3, and this includes power consumption considerations (at system level, which is what matters). Considering the price difference and the 3rd core, I would not consider the low-end sandy bridge for my budget PCs.
CeriseCogburn - Thursday, January 3, 2013 - link
Exactly, and that newer platform has a gigantic upgrade path years from now while the amd system has jack nothing.When the company wants to throw the systems away, all the employees will want one because they can drop a 2500K in it for the $50 it will cost then, and have a freaking screamer of system again. Or one of the new IB's.
The amd boards won't make it in tact to the trash bin. No one will want them.
TypeS - Thursday, August 25, 2011 - link
Brand recognition, plain and simple. That is why Intel releases these chips and why they will sell. Agree with the ways Intel has grown in the last 2 decades, they have the market leader spot and will use it. Intel was the company that created the x86 design and AMD would be nothing today without it's tech and government forcing cross-licensing agreements down Intel's throat.Remember the percentage of us that actually read these reviews, go to these websites and know that actual statistics of all the various PC components is pretty small compared to the size of the consumer market. People usually walk into a Best Buy (or other big box store) and see two things to base their decisions on, brand and price.
You see the same with cars. People buy the ridiculously overpriced german, italian and bristish "luxury" cars when the same quality can be found in premium Japanese cars and some luxury American models. It's brand recognition. Who wins in performance charts means little in the end.
CeriseCogburn - Thursday, January 3, 2013 - link
A few year down the line in hoes the IB or 2500K or 2600K and suddenly the piece of crap is a MONSTER.The amd board - stomp it. It loses, screw any upgrade.
Oh look at that... only a freaking fool would buy the amd rig now.
JD_Mortal - Monday, May 6, 2013 - link
Because 90% of computer users only do "basic stuff" with thier computers.Because, AC is more expensive than heat.
Because having 2000 computers that constantly draw 95Watts at idle, and not being used, is more expensive to operate for four years, than 2000 running at 23Watts at idle.
Because "We" (the people buying them, who are the majority of sales), keep asking for it. Thus, fueling the few sales and development of YOUR overpriced and over powered (wattage-power), making them within your actual budget. (Without OUR sales, YOUR chips would still be on 65nm, and cost $1000 per CPU. Oh, you are welcome BTW.)
algida79 - Tuesday, August 23, 2011 - link
Hi Anand. I think that the phrasing under the x264 comparison charts:"Without Quick Sync, the Pentiums have to rely on raw CPU power for video encoding performance."
is a bit misleading. It implies that the presence of QuickSync would benefit the Pentiums' performance in x264 encoding, which is not the case.
Anand Lal Shimpi - Tuesday, August 23, 2011 - link
Very true - fixed :)Take care,
Anand
Arnulf - Tuesday, August 23, 2011 - link
How about that par2 test, is it true that the lower clock A6-3650 is faster at this one than A8-3850 ?ckryan - Tuesday, August 23, 2011 - link
But I don't think the celeron line deserves to continue.These Pentiums aren't unattractive neccessarily. If you think about it, they're faster than a comparable i3-5xx series, have better IGPs and use less power. You can't over clock them, nor can they hyperthread, but they're not useless. The celeron line refresh is a different story -- though I suppose you could say the 1155 celerons are the best ever... not that it's saying much. I have a spare 1155 H67 board laying around that could be inexpensively outfitted with a Pentium for not much cash, but the question remains whether the Athlon II X3 it would replace would be better served by retirement. The answer is probably no -- it's not worth the $78 for a lateral move. If you're building a budget system from scratch you'll probably need to decide whether a super cheap H61 board and a Pentium is a good investment, and I think most people would be better served with an Athlon II system if you can't fit Llano or a H67/z68 i3 setup into your budget. But if you're in the market, a G620/H61/4GB DDR3/Rosewill Case and PSU combo is less than $200 at Newegg. So I'd say buy whatever is on sale. Add $120 for a cheap SSD and DVD burner and you have a system that could do everything but game, or choose to get a entry level GPU like the 6600 series and you could game pretty well for such a modest system.
CeriseCogburn - Monday, June 25, 2012 - link
The problem with your thinking is after some time one can drop a 2500K SB in the dirt cheap pentium board and be miles ahead of any amd setup, which cannot and will not do the same thing.So if you go amd you've screwed yourself forever.