Broadwell-K i7 5775C/i5 5675C

[Dave2150]

So, finally the clock speeds and cache size have been leaked:



Looks very disappointing for anyone who was waiting for these, or Z97 owners who assumed the 5th generation of I7's would have better performance than the 4th generation.

Compared to the 4790k, the top Broadwell CPU (I7 5775) has 2MB less of L3 cache, 700Mhz lower base clock and 700Mhz lower turbo clock.

The only saving grace for these CPU's will be the 128MB of L4 cache (Iris Pro) which can be utilized to aid CPU performance when a discrete GPU is installed. Anandtech calculated this to offer rough 10% extra performance in most CPU tasks.

Intel quote Broadwell to be a 5.5% IPC increase over Haswell. When coupled with the 10% from the 128MB l4 cache will provide an estimated 15.5% IPC increase, though I highly doubt actual benchmarks will actually demonstrate this, probably more like a 7% increase combined.

Source: http://chinese.vr-zone.com/146637/intel-lga-1150-broadwell-for-desktop-only-have-i7-5775c-and-i5-5675c-03232015/

Also doesn't bode well for Skylake that their 14nm process has regressed clock speed so severely, though maybe they'll have a better silicon process for those chips.

 

[Dave2150]

What's the C denote?

And I'm not sure why anyone would expect anything more than ~10% improvement. It's actually better for everyone that they don't go crazy and violate AMD.
The next logical step for Intel basically makes AMD all but redundant. (I3's becoming what we know as i5's, the i5's becoming what we know as the i7 X7XX and then the i7 becoming a hexcore)

I don't know why people get hyped for Intel launches at the moment....

Although, pretty sure your figures are all wrong

No idea what the 'C' means. These CPU's are unlocked parts, however. Unknown why the dropped the 'K'.

Which figures do you believe to be wrong?

Intel stated that Broadwell is on average a 5.5% IPC increase from Haswell.

With 700Mhz less clock speed than the 4790k, 2MB less l3 cache, I very much doubt this CPU will equal it in performance.

As I said above, the only unknown at the moment is the 128MB l4 cache, Anandtech estimated this to give on average a 10% performance increase.

Though I still don't think this l4 cache will be enough to let it equal Devil's Canyon in performance.

 

[Dave2150]

Seems that LGA1150 Broadwell chips are the direct successors to the 4770R (http://ark.intel.com/products/76642/Intel-Core-i7-4770R-Processor-6M-Cache-up-to-3_90-GHz?q=4770R).

Exact same CPU on 22nm Haswell, though the Haswell part had higher turbo clocks.

Interestingly, the 4770R has the same TDP, 65W, suggesting the die shrink to 14nm netted them absolutely nothing - clock speeds are lower than on Haswell, and TDP is the same.

I guess they didn't do a 4790k successor due to the 14nm process clocking worse than Haswell did, so it would be impossible for them to make a faster CPU than the 4790k.

 

[Dave2150]

Chances are these will work on z87 chipset and not only z97 if the changes are that small.

Chances are that no-one on Z87 or Z97 will even care, as this CPU is very unlikely to outperform the 4770k or 4790K, imo.

It's clocked slower than both parts, has 2MB less L3 cache than both parts.

The only thing it has going for it is the 128MB of l4 cache.

Hopefully these clock speeds are not final, maybe there are engineering sample clock speeds.

 

[Dave2150]

Also, you can't just add percentage increase from two sets of gains as in the OP. For example, if IPC improves by 10% and clock speed improves by 10%, the total increase would be 21%, not 20% (assuming linear performance increase per clock cycle, which isn't quite true usually).

My estimates in the OP are just rough estimates. The only concrete figure we got from Intel was the 5.5% IPC increase over Haswell. This was without the 128MB l4 cache.

 

[Dave2150]

I can't help thinking about Skylake. For all the much-trumpeted 15-20% IPC increase that we are allegedly going to see, it is no gain if the chips are 10-15% lower clockspeed than Haswell.

Wouldn't surprise me if Skylake is launched only for mobile/tablet etc this year, and Desktop will come next year, when the 14nm process is capable of higher clocking parts.

My god we've been stuck on 22nm Haswell's for what seems like infinity, almost as bad as the 28nm node GPU's are stuck on.

 

[Dave2150]

Damn... there was me last week starting to get mildly excited about Broadwell.
See http://forums.overclockers.co.uk/showthread.php?t=18659159

Especially when dave2150 said

"So I guess it's quite possible Broadwell-K will be able to smash the 4790k's performance, when taking into account the extra 128MB l4 cache that can be used for CPU performance "

O'well...

Ye, we all assumed Broadwell would be superior to Haswell (DC), sadly it won't be and we'll have to wait for Skylake.

 

[Dave2150]

Anybody consider the possibility that these leaks are false and now people are disappointed, they'll just buy up the last remaining Haswells?


Naah

Intel made a statement confirming these CPU's are 65W and are designed for Mini PC's, all in ones etc.

This 65 watt unlocked desktop processor, available mid-2015, will bring new levels of performance and power efficiency to Mini PCs and desktop All-In-Ones.

http://blogs.intel.com/technology/2015/03/gdc-2015/

The only strange thing here is that these Broadwell chips are unlocked models. Why Intel would unlock CPU's that are designed for thermally constricted cases is very strange - though I assume it's just so Z97 owners can have a new toy to play with.

Maybe they'll turn out to be overclocking monsters, and do 5Ghz on air, though I highly doubt it

 

[Dave2150]

So is the eDRAM used for CPU as well or only gaming IGPU?

Used to speed up CPU calculations, if you're using a dedicated GPU. Anandtech previously tested this on a Haswell version with Iris Pro, it provided roughly 10% more performance compared to without it.

 

[Dave2150]

We should be engineering samples of these soon, if they release date is correct.

Hopefully there will be benchmarks to look at, so we can see how much of a difference the 128MB L4 cache (Iris pro) makes.

 

[Dave2150]

I'm really interested to see how these new processors perform. I've been forced into an upgrade up to Z97 after my Z77 board failed and I definitely want to jump up to an i7. Will be interesting to see if there are any significant performance gains firstly over my i5 3570k, and then obviously over the i7 4790k. If not, then I know what I'll be buying.

Any chances Broadwell will be any cheaper than Haswell? Especially since it's looking to offer less performance.

Yeh, I'm also very curious to see the performance data.

I guess the main issue is how well these new CPU's will overclock. This will be our first socketed 14nm CPU to overclock, so we're treading new water here.

It may very well be that the 14nm process is a better overclocker than the 22nm haswell process - as these new CPU's may have been simply limited to these clocks due to them being aimed at small factor/mini PC's, so the 65W may have been the maximum TDP they wanted to release.

Or it may be a terrible overclocker, we'll have to wait and see.

Loosing 2MB L3 cache over the 4790k should affect some apps/games quite a bit, though the performance implications of the 128MB l4 cache remains to be seen - Anandtech claimed roughly 10% performance improvement from the Haswell CPU's that had this 128MB cache.

WTB some engineering sample leaks!

 

[Dave2150]

Still no news - the way things are looking, Broadwell for desktop will be released the same time as Skylake!

 

[Dave2150]

But the first Skylake CPU's will be the slower, locked ones. So enthusiasts, who don't want/need 6&8 core CPU's, will still prefer the Devils Canyon i5 & i7 and possibly Broadwell, depending on benchmarks, until the full fat, unlocked Skylakes arrive in 2016.

I will only upgrade to the i7 Broadwell if it can clock to at least 4.5Ghz and is at least 5% quicker in terms of IPC than my current 4690k, otherwise I'll wait for the 2016 Skylakes before upgrading again.

All leaked info points so the simultaneous release of Skylake LGA1151 skews.

So, assuming the leaks are accurate, the unlocked chips should be available day1.

 

[Dave2150]

So if Broadwell 5775C is not really better than a 4770K or 4790K what exactly is the point of the release at this time? I am not sure I see the commercial niche that Intel is going for here.

Intel said that these two Broadwell CPU's are aimed for mini PC's, smaller factor PC's etc - PC's without a dedicated graphics card, hence the special 'iris pro' GPU with 128MB of eDRAM.

So in other words, they are not meant to compete with the 4790k, and are for an entirely different purpose.

I am however very interested in seeing how well these CPU's overclock, as it's our first go at overclocking on Intel's new 14nm process.

 

[Dave2150]

would have been nice of Intel to tell people this before they went ahead and bought into Z97 thinking they would get 4770K / 4790K replacements with Broadwell. Z97 was touted as supporting Broadwell, what they didn't tell us was we were only getting 2 chips..

Even worse as Devil's Canyon is supported on older than Z97 mobo's. Literally a pointless upgrade if they don't bring anything decent to desktop with Broadwell.

Bit dodgy, we got stitched up good and proper lol. Guess they want everyone to buy another mobo for Skylake instead. Yup thanks Intel

Intel covered themselves, as there will be Broadwell desktop CPU's (all 2 of them). They must have assumed people would expect a 4790k successor though, so yeh I agree it's very disappointing for those who bought z97 with a mind to upgrade to Broadwell down the road.

Though, we still don't know how well this 14nm process overclocks, though I highly doubt it will clock as high as the 4790k. We could be surprised.

We also don't know how much the 128MB eDRAM L4 cache will affect things, so there may be a glimmer of hope for Z97 users, albeit a rather weak one.

 

[Dave2150]

Update:

Broadwell-C (k) pictured:



Along with an updated roadmap:



Broadwell-C April, May and June (Q2)

Skylake-k July, August and September (Q3)

Broadwell-E January, February and March (Q1 2016)

Source: http://diy.pconline.com.cn/637/6375701.html

-------------------------

So, not long at all to wait for Broadwell-C, Skylake-K coming on time in Q3 and of course Broadwell-E next year.

Nice to see new CPU's are almost here

 

[Dave2150]

Woah... that couldn't be the back of the processor could it? What happened to all those pins? If that is an actual Broadwell-C, then it may use a new chipset? How will that thing fit into existing boards? I'm shrugging that image off as either concept art or fake. It's too strange... *shudder*

As Sylver mentioned, it's the top of the CPU, though without it's IHS. Looks to be a load of capacitors or resistors alongside the large die.

 

[Dave2150]

First engineering samples are starting to leak out!



Pretty useless until we know the cooling and voltage used, also bear in mind the 5775C has only 6MB of cache.

 

[Dave2150]

I7 5775C clocked to 5.0Ghz... Remember when Boomstick (Moi) said all hope was not lost

All hope is still lost, since this wasn't stable even with 1.419V (suicide run) on air. All he was able to do was take a screenshot before it crashed.

Seems very similar to the 4790k overclocking, at least overclocking hasn't deteriorated even further from the 22nm node.

All that's left to see is how the 128MB of eDRAM will affect things, though remember these only have 6MB of L3 cache, so I suspect it will balance out the performance.

I'm much more interested in Skylake at this point, since we get the vastly improved Z170 chipset, with much greater PCI-E lanes for SSD's.

 

[Dave2150]

Disagree, these chips look like an alternative to 4770K / 4790K without having to switch mobo or buy DDR4 like you do with Skylake.

If they can reach 4.8Ghz > 5.0Ghz on air they def have potential, especially if they run cooler.

Disagree - these are bound to be sold at a premium, due to the most expensive IGPU onboard - Iris Pro. These chips are designed for use without a dedicated GPU - something that rules out the majority of users here.

It's horses for courses mate - no room for a dedicated GPU? Then these chips will get you the best onboard graphics money can buy, doubt it's going to be cheap though.

For everyone else who's going to be using a dedicated GPU, 4790k or Skylake or X99 is a much better choice.