[Sweclockers] Broadwell i5 and i7 compared

[Mondozei]

A breakout star of recent Skylake reviews has been the Broadwell CPU(s).

Sweclockers were slightly different from most sites in that they had an i5 - not an i7 - Broadwell to compare and in their Skylake review it did extraordinarily well.

They promised they would get back to their readers with an i7 and do a thorough test. Here it is.

I linked to their start of the game benchmarks. You don't need to know Swedish to know what is going on.

From the looks of it, it seems like the i7 Broadwell is a lot less different than the i7 Skylake. The i5 Broadwell is significantly better than the i5 Skylake, however.

Note that they use a 980 Ti, which of course makes the CPU count all that much more.

 

[DrMrLordX]

Maybe Swedes can actually buy Broadwell-C. Too bad it's MIA in the states, yo.

 

[coercitiv]

Maybe Swedes can actually buy Broadwell-C. Too bad it's MIA in the states, yo.

Every time anyone mentions desktop Broadwell performance numbers someone comes in and mentions availability/price problems in USA.

I understand your predicament (not yours personally, US folks in general) but you also need to understand there are other countries where this CPU is available and similarly priced to Skylake. In fact, all costs considered, system ends up being cheaper, at least for the time being.

If building a gaming machine and target CPU is the i5, one should take a serious look at Broadwell if available.

From the looks of it, it seems like the i7 Broadwell is a lot less different than the i7 Skylake. The i5 Broadwell is significantly better than the i5 Skylake, however.

And all this is done with a lower TDP. Put them on equal footing power wise and things could really get out of hand.

Skylake needs eDRAM badly. Good thing the controller is in there already.


Same clocks.

All platforms overclocked.

 

[richierich1212]

Every time anyone mentions desktop Broadwell performance numbers someone comes in and mentions availability/price problems in USA.

6700K MIA too :biggrin:. I'd definitely pick up a 5675C over 6600K right now since I already have a Z97 motherboard and just mainly use that computer for gaming with my sons.

 

[DrMrLordX]

Every time anyone mentions desktop Broadwell performance numbers someone comes in and mentions availability/price problems in USA.

I understand your predicament (not yours personally, US folks in general) but you also need to understand there are other countries where this CPU is available and similarly priced to Skylake. In fact, all costs considered, system ends up being cheaper, at least for the time being.

If building a gaming machine and target CPU is the i5, one should take a serious look at Broadwell if available.

Actually, I think it's all of North America, and probably Central/South America as well. Sorry if it comes off as snarky and privileged but it's true, and unfortunately English-speaking forums feature a lot of people who are affected by this dearth of Broadwell-C CPUs.

At least the 6700k should be hitting the States "real soon now". Last time I heard anyone give a date for availability of Broadwell-C in North America, they said November. It may never be sold here, sadly.

And all this is done with a lower TDP. Put them on equal footing power wise and things could really get out of hand.

Indeed. Skylake looks pretty bad in comparison, really. Or is it that Broadwell just looks like a wonderful chip? I don't quite know what to make of it. There's still the issue of memory used (in theory, DDR4 at high clockspeeds could close the gap between Skylake and Broadwell-C) and other stuff like that thar.

For people looking to hold on to DDR3 and use it on Z97, Broadwell-C should be awesome. Even with a 4.2 GHz clockspeed ceiling (which several have breached, mind you), it should be a fantastic chip. Hell I would even seriously consider getting an i7-5775C if they saw fit to sell me one. The only reason I'd hesitate is that Gen8 doesn't feature GPGPU task pre-emption and task scheduling (Gen9 does).

 

[ShintaiDK]

The 5775C seems to currently be more or less sold out here in Scandinavia.

5675C is still in some supply. Retailers say they sell like hotcakes currently. I assume people have gotten their eye on the EDRAM bonus.

Z170+Skylake+DDR4 is getting hard to find now as well.

 

[Dufus]

Maybe Swedes can actually buy Broadwell-C. Too bad it's MIA in the states, yo.

The D-1540 is being refreshed in November with the D-1541. Maybe there's a refresh on the way for the i7-5775C, one with better overclocking. One can only hope.

 

[Sweepr]

Looks at RAM choice:

16 GB (2x 8 GB) Corsair Vengeance LPX DDR4
2 133 MHz, 15-15-15-36
Intel "Skylake"

According to PCLab and Hardware.fr Skylake and Broadwell-K offer basically the same performance per clock in games, coincidentally or not both websites tested Skylake with faster RAM.

 

[coercitiv]

Looks at RAM choice for Broadwell:

16 GB (2x 8 GB) Corsair Vengeance Pro DDR3
1 600 MHz, 9-9-9-24
Intel "Haswell", "Broadwell", "Ivy Bridge"

According to PCLab and Hardware.fr Skylake and Broadwell-K offer basically the same performance per clock in games, coincidentally or not both websites tested Skylake with faster RAM.

Let's see what happens when both platforms get fast memory. According to hardware.fr Broadwell i5 is faster clock for clock that Skylake i5 even with DDR4 2800 CL15.

Faster DDR4 cancels some of the advantage of eDRAM caching, but even at stock clocks Broadwell i5 is faster than Skylake i5 in the Hardware.fr tests.

Games love i5 5675C.

 

[Sweepr]

Looks at RAM choice for Broadwell:

Let's see what happens when both platforms get fast memory. According to hardware.fr Broadwell i5 is faster clock for clock that Skylake i5 even with DDR4 2800 CL15.

Faster DDR4 cancels some of the advantage of eDRAM caching, but even at stock clocks Broadwell i5 is faster...

Games love i5 5675C.

A hair faster (1.6%), just like Skylake at PCLab. But eDRAM is really great for games, will be a welcome addition to Skylake next year.

 

[coercitiv]

The only reason I'd hesitate is that Gen8 doesn't feature GPGPU task pre-emption and task scheduling (Gen9 does).

Hopefully I won't have to make this choice, as I'm an almost exclusive laptop user, and my Skylake upgrade will include eDRAM.

 

[sm625]

Imagine how fast an intel chip could be if they got rid of 3/4 of their gpu and quadrupled all the caches. It would be the same size but one heck of a lot faster.

 

[LTC8K6]

Imagine how fast an intel chip could be if they got rid of 3/4 of their gpu and quadrupled all the caches. It would be the same size but one heck of a lot faster.

Quite a few have a Xeon counterpart that doesn't have the gpu and is cheaper.

 

[DrMrLordX]

The D-1540 is being refreshed in November with the D-1541. Maybe there's a refresh on the way for the i7-5775C, one with better overclocking. One can only hope.

A refresh for Broadwell-C would be eccentric, but welcome. Maybe as a stop-gap leading up to desktop Skylake GT4e or . . . something.

Hopefully I won't have to make this choice, as I'm an almost exclusive laptop user, and my Skylake upgrade will include eDRAM.

I expect we'll probably see GT4e first in laptops. Possibly thanks to Apple.

 

[CHADBOGA]

Will Intel be saving eDram on Skylake, till they get to Kabylake?

 

[know of fence]

Anand has talked on the podcast about how having really fast embedded RAM is the next big thing for CPUs. Intel also obviously knew about the massive improvements in discrete gaming when they marketed the Haswell/CRystal Well with eDRAM back in 2013.

This is from one of their slides in a 2013 presentation, from the Haswell Chief Architect. People may say that faster DDR4 will make a difference, it won't. Actually those kits will have even slower timings. Latency is the big deal here, when a GPU has to render a frame every 8300 nanoseconds, having a memory latency of either a 100 or 50 makes a bit difference for CPU limited frame time spikes.
Sharing eDRAM with bandwidth starved integrated graphics sounds like the CPU has to wait and get in line, which is perhaps why we saw very inconsistent results with the first Iris Pro. I wonder how it works: 128 MB is what I used to allocate for on-board graphics or is it a shared space like AMD's HSA.

 

[ShintaiDK]

Will Intel be saving eDram on Skylake, till they get to Kabylake?

Well we will always get the EDRAM GT3e/GT4e models as always.

We know all Skylake dies got an EDRAM controller. So the big question is what is the strategic purpose. Because its not there by accident. Xeon GT2 models would be a high candidate for defacto EDRAM.

But we have to see what the management got in their plans. However I think we are getting close to a full broad EDRAM equipped range.

 

[Idontcare]

Well we will always get the EDRAM GT3e/GT4e models as always.

We know all Skylake dies got an EDRAM controller. So the big question is what is the strategic purpose. Because its not there by accident. Xeon GT2 models would be a high candidate for defacto EDRAM.

But we have to see what the management got in their plans. However I think we are getting close to a full broad EDRAM equipped range.

Seems like they should just create a bunch of SKUs and interleave them throughout the existing i3/5/7 stack the same they do with core counts and hyperthreading active/inactive.

If I have the choice of buying a 4C/4T 6600K or a 4C/8T 6700K then why not have the choice of buying a 4C/8T 6800K that comes equipped with edram?

 

[ShintaiDK]

It could be part of the "refresh".

 

[CHADBOGA]

Getting faster officially supported ram and equipping models with Edram will certainly soften the blow of having to wait so long for 10nm processors.

 

[NTMBK]

Getting faster officially supported ram and equipping models with Edram will certainly soften the blow of having to wait so long for 10nm processors.

I wouldn't be surprised if this were true. There's no competitive pressure from AMD, so no need to bring out their best parts straight away.