What is the Lynnfield i5 equivalent to i7 920 ?

[sorinm]

I want someone to clear this up for me...

In the tests I have seen on the www, Lynnfield 2.66 Ghz = Core i7 920 but

i7 920 is about 280 $
Lynnfield 2.80 Ghz will cost 280 $


Does this mean that I should wait until september to build an i5 rig or am I wrong and i7 920 = Lynnfield 2.80 Ghz and I could build the i7 rig right now ?

What do you advice me to do ?

 

[flyin15sec]

Processor price alone doesn't show the whole picture. You have to account for all the other parts needed, motherboard price, low voltage DDR3 dual channel kits. As it is, now, I'd wait till i5 is release first.

 

[WR2]

What is your overall budget? What are you going to use the PC for?

 

[sorinm]

I`m not a gamer, I want to build a future proof rig that will serve as my home pc. Music, Video, Office and C++, visual basic compiling


Let`s ignore the difference of price. I don`t think P55 MB will be more expensive than actual X58 MB

I`ll get only 4 Gb of RAM for i5 and not 6 like i7 needs

A difference of 50 $ between 2.80 Ghz Lynnfield and i7 920 is not a problem.


Do you think 2.80 Ghz lynnfield will be more powerfull than 2.66Ghz 920 ?


I`we had only my first PC on intel platform, P3 550 Mhz, since then I`ve had only AMD platforms and I want to switch back to intel.
I`m starting to have doubts and intel is confusing me right now, the simplest way for me now is to get an AM3 955 BE platform, but I don`t want to regret what I would miss if I5 is such a winner

 

[Helloworld_98]

^ take in mind that the $284 i5 is bulk price so expect to pay over $300 retail.

and then supposedly $160 for the mobo, you end up paying a bit more for the i5 than the i7 as long as you get a mainstream board for the i7 like the MSI X58M.

 

[Bluescreendeath]

A huge advantage i7 has is QPI?

I think the i5 doesn't have QPI, and uses DMI? DMI is similar in performance to 775 mobo's FSB.

 

[fazers_on_stun]

I`m not a gamer, I want to build a future proof rig that will serve as my home pc. Music, Video, Office and C++, visual basic compiling


Let`s ignore the difference of price. I don`t think P55 MB will be more expensive than actual X58 MB

I`ll get only 4 Gb of RAM for i5 and not 6 like i7 needs

A difference of 50 $ between 2.80 Ghz Lynnfield and i7 920 is not a problem.


Do you think 2.80 Ghz lynnfield will be more powerfull than 2.66Ghz 920 ?


I`we had only my first PC on intel platform, P3 550 Mhz, since then I`ve had only AMD platforms and I want to switch back to intel.
I`m starting to have doubts and intel is confusing me right now, the simplest way for me now is to get an AM3 955 BE platform, but I don`t want to regret what I would miss if I5 is such a winner

Intially the P55 mobos will not be cheap, but they should drop in price rapidly depending on how well the i5 sells. Since Intel is coming out with it in September, I'd expect a large number of holiday sales so that might be your prime time to get a system, plus give the manufacturers some time to fix up their initial BIOS issues. Anandtech thinks P55 mobos should be under $100 eventually.

Seriously, unless you are sticking with a 32-bit OS, I'd go for 8 GB of memory - DDR3 is fairly cheap nowadays - saw somebody stating they got 6 gigs for $85, which seems incredible to me but then I haven't been looking . Anyway, the i7 doesn't *force* you to use tri-channel - you can populate the board with one or two or three sticks if you want. Some of the early i7 reviews compared dual-channel performance to tri-channel performance (and for DT apps, didn't find much difference).

With Win7 around the corner, I'd definitely stick to hyperthreaded CPUs given your usage scenario, so avoid the cheapest i5 as Intel disabled HT on it. Intel and MS seem to be gunning for big holiday sales with their timing, so if you can wait about 4 months or so, you'd be set.

 

[fazers_on_stun]

A huge advantage i7 has is QPI?

I think the i5 doesn't have QPI, and uses DMI? DMI is similar in performance to 775 mobo's FSB.

True - QPI is something like 8 times the bandwidth of DMI, but then i5 has the PCIE interface directly on the CPU for lowest latency. Personally I'd wait until somebody gets more than a very early ES sample which is what Anandtech used.

 

[Helloworld_98]

^ that doesn't make sense that QPI is 8x DMI, because QPI is 2x the bandwidth of FSB.

 

[fazers_on_stun]

^ that doesn't make sense that QPI is 8x DMI, because QPI is 2x the bandwidth of FSB.

From the Anandtech article:

Intel’s QPI is a very fast bus delivering up to 25.6GB/s of bandwidth...

If you’ve got a multi-socket system (e.g. dual processor Xeon workstation, or Skulltrail successor) or if you’ve got a lot of high bandwidth PCIe devices (e.g. multi-GPU or lots of Larrabees) then QPI makes a whole lot of sense. However, if you’ve got a single socket system and aren’t running a lot of high bandwidth PCIe devices then QPI is overkill.

Intel’s DMI is the link used between the X58 chipset and the ICH10 I/O controller, it’s a much more conservative bus capable of delivering 2 - 4GB/s of bandwidth. That’s enough bandwidth for things like SATA and USB but a single PCIe x16 slot can deliver 16GB/s of bandwidth, far too much for Intel’s DMI.

It's been a while since college , 25 divided by 3 (halfway between the 2 ~ 4GB/s disclosed for DMI), is about 8.

 

[archibael]

A huge advantage i7 has is QPI?

I think the i5 doesn't have QPI, and uses DMI? DMI is similar in performance to 775 mobo's FSB.

QPI's kind of irrelevant in this context. In the i7 it serves two purposes: 1) to connect to other i7s in dual socket systems and 2) to connect to the northbridge. Since the i5 is a single-socket chip and has essentially moved the entire northbridge onto the CPU die, QPI would serve no purpose for i5.

DMI connects the northbridge to the southbridge in both systems. The X58 connects to the ICH10 with DMI in exactly the same way that i5 connects to the PCH aka IbexPeak. It's a wash.

 

[WR2]

Do you think 2.80 Ghz lynnfield will be more powerfull than 2.66Ghz 920?

Depends more on the software packages and how you use them then the actual clock speeds of the CPUs.
If you're multi-tasking with several multi-threaded software packages Im guessing the better option is the Core i7. If you're using most of the currently available software and only lightly multi-tasking the higher clocked CPU
would have the advantage.
That Anandtech article is the best guidance currenly available.
My suggestion is to compare the identically clocked CPUs and use that for making your decision. It's very easy to bump those CPUs up to match the highend $1000 CPUs.

 

[Bluescreendeath]

QPI's kind of irrelevant in this context. In the i7 it serves two purposes: 1) to connect to other i7s in dual socket systems and 2) to connect to the northbridge. Since the i5 is a single-socket chip and has essentially moved the entire northbridge onto the CPU die, QPI would serve no purpose for i5.

DMI connects the northbridge to the southbridge in both systems. The X58 connects to the ICH10 with DMI in exactly the same way that i5 connects to the PCH aka IbexPeak. It's a wash.

Hmm I see. What makes i7 2.66Ghz CPUs faster than i5 2.66GHz CPUs then? (even if both have Hyperthreading)

If QPI doesn't give i7s a huge advantage, what are the other advantages of i7?

 

[fazers_on_stun]

Hmm I see. What makes i7 2.66Ghz CPUs faster than i5 2.66GHz CPUs then? (even if both have Hyperthreading)

If QPI doesn't give i7s a huge advantage, what are the other advantages of i7?

Well the i7 name is about 40% higher than i5 .

One advantage would be that the i7 mobos and BIOS versions would be more mature than those for the brand-new i5's. Also, the cheapo (2.66GHz) i5 has hyperthreading disabled - you have to step up to the same-priced 2.8GHz version to get HT. That's about it, since for DT use tri-channel vs. dual-channel doesn't seem to make a lot of difference according to the benchies I've seen.

 

[sorinm]

thanks for your answers, I`m prepairing the terrain for the new rig, i7 or Lynnfield if I can wait until september

I bought a SIRTEC HP-850-G14C PSU and a SPIRE BlackFin case
I also have bought 2x Samsung SpinPoint F1 1TB in RAID0, I hope it will be fast enough

 

[archibael]

Hmm I see. What makes i7 2.66Ghz CPUs faster than i5 2.66GHz CPUs then? (even if both have Hyperthreading)

If QPI doesn't give i7s a huge advantage, what are the other advantages of i7?

i7 has eleven herbs and spices, while i5 only has ten.

 

[Bluescreendeath]

^ The only problem is i7 might be out of stock/totally sold out by the time i5 gets here...

Is that a possibility?

 

[sorinm]

+1 for Lynnfield is the fact that some mobos might have SATA 3 or USB 3 support, more futureproof. SATA 3 won`t be such a step forward since actual SSD`s and HDD`s don`t` reach SATA 2 maximum capacity but USB 3.0 ...

-1 for P55 is the fact that you can`t SLI/CROSSFIRE X16 X16, but you have eighter 1 PCIE X16 or 2 PCIE X8


decisions ..

 

[IvanH]

Well the i7 name is about 40% higher than i5 .

One advantage would be that the i7 mobos and BIOS versions would be more mature than those for the brand-new i5's. Also, the cheapo (2.66GHz) i5 has hyperthreading disabled - you have to step up to the same-priced 2.8GHz version to get HT. That's about it, since for DT use tri-channel vs. dual-channel doesn't seem to make a lot of difference according to the benchies I've seen.

Acording to
http://www.pcgameshardware.com/aid,691811/Lynnfield-tested-Intel-Core-i5-750-and-Core-i7-860-benchmarked-in-Anno-1404-Dawn-of-Discovery/Reviews/

I7-920 has 2.4GHz FSB/HT frequency whereas I7-8xx has 2.13GHz FSB/HT frequency. Maybe that has something to do with the different performance.

 

[amdfangirl]

No, just wait and see what happens?

 

[viruscece]

+1 for Lynnfield is the fact that some mobos might have SATA 3 or USB 3 support, more futureproof. SATA 3 won`t be such a step forward since actual SSD`s and HDD`s don`t` reach SATA 2 maximum capacity but USB 3.0 ...

-1 for P55 is the fact that you can`t SLI/CROSSFIRE X16 X16, but you have eighter 1 PCIE X16 or 2 PCIE X8


decisions ..

well they put 9800gx2 in SLI in 8x + 8x and 16x + 16x and the difference between them was + 5 frames for x16 in crysis, if the 5 frames don't put you down it's ok, but it's not future proof that is for sure.

 

[theholylancer]

ladies and gentlemen of the forum regulars, lets take an cut and paste approach to I5s (or any other future tech buying advice) with:

The future is uncertain, we can help you with information that we know, but that can be FUD for all we know. If you want certainty, buy now with what is on the market. Thank you.