The Sandy Bridge Preview
by Anand Lal Shimpi on August 27, 2010 2:38 PM ESTOverclocking Controversy
It wasn’t until the Pentium II that Intel started shipping multiplier locked CPUs. Before then you could set the multiplier on your CPU to anything that was supported by the line, and if you had a good chip and good enough cooling you just overclocked your processor. Intel’s policies changed once remarking, the process of relabeling and reselling a lower spec CPU as a higher one, started to take off.
While multipliers were locked, Intel left FSB overclocking open. That would be an end user or system integrator decision and not something that could be done when selling an individual CPU. However, ever since before the Pentium III Intel had aspirations of shipping fully locked CPUs. The power of the enthusiast community generally kept Intel from exploring such avenues, but we live in different times today.
Two things have changed Intel’s feelings on the topic. First and foremost is the advent of Turbo Boost. So long as Intel doesn’t artificially limit turbo modes, we now have the ability to run CPUs at whatever clock speed they can run at without exceeding thermal or current limits. We saw the first really exciting Turbo with Lynnfield, and Sandy Bridge is going to expand on that as well. On the flip side, Intel has used Turbo as a marketing differentiator between parts so there’s still a need to overclock.
The second major change within Intel is the willingness to directly address the enthusiast community with unlocked K-series SKUs. We saw this recently with the Core i7 875K and Core i5 655K parts that ship fully unlocked for the overclocking community.
The K-series SKUs, these will be more important with Sandy Bridge
With Sandy Bridge, Intel integrated the clock generator, usually present on the motherboard, onto the 6-series chipset die. While BCLK is adjustable on current Core iX processors, with Sandy Bridge it’s mostly locked at 100MHz. There will be some wiggle room as far as I can tell, but it’s not going to be much. Overclocking, as we know it, is dead.
Well, not exactly.
Intel makes three concessions.
First and foremost we have the K-series parts. These will be fully unlocked, supporting multipliers up to 57x. Sandy Bridge should have more attractive K SKUs than what we’ve seen to date. The Core i7 2600 and 2500 will both be available as a K-edition. The former should be priced around $562 and the latter at $205 if we go off of current pricing.
Secondly, some regular Sandy Bridge processors will have partially unlocked multipliers. The idea is that you take your highest turbo multiplier, add a few more bins on top of that, and that’ll be your maximum multiplier. It gives some overclocking headroom, but not limitless. Intel is still working out the details for how far you can go with these partially unlocked parts, but I’ve chimed in with my opinion and hopefully we’ll see something reasonable come from the company. I am hopeful that these partially unlocked parts will have enough multipliers available to make for decent overclocks.
Finally, if you focus on multiplier-only overclocking you lose the ability to increase memory bandwidth as you increase CPU clock speed. The faster your CPU, the more data it needs and thus the faster your memory subsystem needs to be in order to scale well. As a result, on P67 motherboards you’ll be able to adjust your memory ratios to support up to DDR3-2133.
Personally, I’d love nothing more than for everything to ship unlocked. The realities of Intel’s business apparently prevent that, so we’re left with something that could either be a non-issue or just horrible.
If the K-series parts are priced appropriately, which at first indication it seems they will be, then this will be a non-issue for a portion of the enthusiast market. You’ll pay the same amount for your Core i7 2500K as you would for a Core i5 750 and you’ll have the same overclocking potential.
Regardless of how they’re priced, what this is sure to hurt is the ability to buy a low end part like the Core i3 530 and overclock the crap out of it. What Intel decides to do with the available multiplier headroom on parts further down the stack is unknown at this point. If Intel wanted to, it could pick exciting parts at lower price points, give them a few more bins of overclocking headroom and compete in a more targeted way with AMD offerings at similar price points. A benevolent Intel would allow enough headroom as the parts can reliably hit with air cooling.
The potential for this to all go very wrong is there. I’m going to reserve final judgment until I get a better idea for what the Sandy Bridge family is going to look like.
Facebook
Twitter
RSS
200 Comments
View All Comments
Anand Lal Shimpi - Friday, August 27, 2010 - link
I don't believe any of these apps have AVX support, they're all too old for that.Take care,
Anand
ESetter - Friday, August 27, 2010 - link
Thank you for the quick answer. It would be great to include some software with AVX support in the full review, when Sandy Bridge launches. Probably the Intel Math Kernel Library will be updated in time.darckhart - Friday, August 27, 2010 - link
1. i'd like to see some temp numbers. along with, does intel stock hsf actually do the job here? (which they have been getting better at really)2. i didnt see anything about accelerated hd video playback using the on die gpu?
3. sure these cpu look great from price point performance gain....until you realize you need a full platform upgrade to go along with it...which if we assume mainstream mobo around the 100$ mark and ram to match since they're taking away the bclk deal... and every 2 yrs is a bit too soon for full platform upgrade imo.
4. hardware virtualization parts? i know the current i3 vs i5/7 chips had some stuff disabled. will these SB chips follow the same profile?
5. mobile versions? we know the mobile ones are usually cut back to fit low tdp profile. will the same cuts apply like the current mobile i3/i5 parts (eg, no real quad core parts)? otoh, what about the quad core mobiles? the current i7 mobile quads are laughable at their performance and heat output (i'm looking at you first gen hp envy). do you think these SB quad mobiles will actually be decent?
DanNeely - Friday, August 27, 2010 - link
Wikipedia lists both 2 and 4 core mobile parts. Not definative but they generally do a good job of keeping up with the latest leaks for things like this.http://en.wikipedia.org/wiki/Sandy_Bridge_(microar...
hamitaltintop22 - Friday, August 27, 2010 - link
I hope there is a price drop for the i5 750 to around $150 when this comes out or i7 920 to $200 (no microcenter here).DesktopMan - Friday, August 27, 2010 - link
I'm not sure about this, but I seem to recall having read that aes-ni instructions use the GPU, at least partially. Makes sense as the gpu is excellent at parallel tasks. If this is the case, would the 6 EU part perform differently than the 12 EU part at AES?Any news on when the inevitable Q67 would launch? I guess it's likely that Q67 will use AMT 6.0 as it was a pretty recent upgrade.
With sata III support at launch you'd imagine they'd also support sata III on their gen 3 SSDs. Time will tell I guess.
overclocking101 - Friday, August 27, 2010 - link
wow bummer. welcome to the end of intel Bus speed overclocking. I will not be adapting the new sockets unless something happens and intel changes their minds. overclocking is not as easy as switching multiplyers even EE cpu's of nowadays show that. 90% of the high overclocks with EE cpus show that a mixture of multi and bus speed is needed. i sense though that with the higher end socket intel will allow it. if not i think its a very bad move on their part.starfalcon - Friday, August 27, 2010 - link
I don't think any of the sandy bridge graphics will be able to get to GT 240 levels.This one trades blows with the 5450 as we can see, and just looking at 3DMark06 scores the 5450 scores about 3500 or so, while the GT 240 does maybe 9000 or 10000.
If the more powerful sandy bridge graphics can get up to 4000 or 5000 or so that would be great, that would be beating the 9400 GT and closing in on the 9500 GT, not getting to GT 240 levels though. Wonder what the next integrated graphics after this will be like.
TETRONG - Friday, August 27, 2010 - link
I take it this means it will soon be the optimum time to purchase current-gen technology at significantly reduced prices?Just wanting to build a no nonsense system at slightly below the current price/performance sweet-spot.
Seems Intel are only interested in toying with consumers.
They've wasted die space that could've been used for a more capable CPU. How many years have we been chained under 4Ghz frequency? 5 years or so?
Nine women can't make a baby in one month! Not every problem is parallelizable - we need greater frequencies/efficiencies.
Now they are locking processors and playing games with the sockets. No USB 3.0!!?
Garbage, No Thanks!!!
Seems you are giving them a free pass Anand. Very convenient timing to steal AMD's thunder, eh!
I love you man - big fan since the beginning, but you should read Scott Wasson over at Tech Report. Those value scatterplots are very helpful to me - these regurgitated press releases, not so much.
Sorry;(
To be so harsh, but we deserve better than these kiddie chips!
Only you can hold them accountable for these failures of imagination.
wyvernknight - Friday, August 27, 2010 - link
I am a bit disappointed. Seems like since intel is wiping the floor with AMD, decided it was OK to screw us all over with this socket thing. I will still buy an intel processor if AMD has no cards to play, but i wont be pleased.