why is an i5 better then my i7 940

[alanwest09872]

just as the title states why is an i5 better then my i7. Recently i looked at windows rating and i had a 7.5 now someone with an i5 had a rating of 7.8. So tell me what the hell is the difference. i thought i7 were the best. Could it be he had his overclocked and i didnt

 

[Tuna-Fish]

i5 and i7 are marketing segment terms, that is, the very fastest processors of each generation are always i7, and the midrange is i5.

It's normal for the midrange of a new processor generation to exceed the top end processors of the last generation. This is what has happened here -- the newest i5 (2500) is better than the processor you have. Of course, the newest i7 (2600) is even better than that.

 

[Tuna-Fish]

I felt this needed to be added: The new generation can be recognized from the 2 in front of the model numbers, for "second generation Intel core processors" or whatever.

Also, if this makes you feel like you should upgrade, hold it off for now -- 940 is close enough to 2600 that it makes little sense to do anything. Also, Later this year Intel will release their new high-end platform, LGA2011, which will replace the LGA1366 which you have. It should have processors that make the performance difference more sensible.

 

[BTRY B 529th FA BN]

The point I have failed to hear is that clock for clock the are pretty darn close. Take off TURBO and that would be a fair comparison. Run them both at the same clock speed and then to me, we are talkin.

 

[Suspicious-Teach8788]

So Sandy Bridge got a massive IPC jump which makes Nehalem look slow? That's pretty much it? I'm curious to IPC numbers because X58 also benefits from huge bandwidth right? 40 lanes vs 24 lanes.... Triple channel.

 

[Cerb]

So Sandy Bridge got a massive IPC jump which makes Nehalem look slow? That's pretty much it? I'm curious to IPC numbers because X58 also benefits from huge bandwidth right? 40 lanes vs 24 lanes.... Triple channel.

No, no, and no. And ni! Ni! Ni!

SB got a fair IPC boost, as far as such close processor generations go, now that we're into diminishing IPC returns. It got much better base and turbo clocks, and more cache, beyond that. It was far more of a boost in power efficiency than in IPC.

PCI-e lanes make no difference, are the same across the socket's CPUs, and I'm pretty sure it's only 16 lanes.

Triple channel makes no meaningful difference on the desktop. It has the potential to make a difference in some serious server workloads (Intel and AMD's high-end server sockets are 4-channel, now), and allows more RAM to be installed.

 

[Zap]

I'm curious to IPC numbers because X58 also benefits from huge bandwidth right? 40 lanes vs 24 lanes.... Triple channel.

The "40 lanes" refer to PCI Express lanes. That has to do with stuff plugged into the motherboard (graphics cards) and not the processor performance itself.

Regarding RAM, socket 1366 supports triple channel DDR3 at 1066MHz data rate while socket 1155 does dual channel 1333MHz data rate. Almost within spitting distance of each other for pure bandwidth.

The other thing is that Sandy Bridge can hit much higher clocks than Nehalem.

Oh yeah, BTW go read up on HardOCP's triple GPU performance article plus the "redux" article. Going from Nehalem to Sandy Bridge with three GTX 580, they saw a big performance boost. It's gotten people arguing in the video forum here. Then again, that's normal.

 

[john3850]

Regarding RAM, socket 1366 supports triple channel DDR3 at 1066MHz data rate while socket 1155 does dual channel 1333MHz data rate. Almost within spitting distance of each other for pure bandwidth. {agreed at stock speed}

I running a 200blck to match my 1600 ram so the extra bandwith can only help.
I have seen 7+ cores at 60% usage being used while gaming on a x58 board.
I could justify getting i7x1155 and hope it can do 5000+mhz.
Now how much difference can there be from i5 at 4800 to 930 at 4200.

 

[betasub]

I'd worry more about the performance in productivity apps and/or games than some contextless figure like Microsoft's WEI.

 

[Barfo]

u mad bro?

 

[Cyanian]

A Sandy Bridge i5 could definetly be faster than an older intel generation i7.

 

[aphelion02]

The point I have failed to hear is that clock for clock the are pretty darn close. Take off TURBO and that would be a fair comparison. Run them both at the same clock speed and then to me, we are talkin.

That makes no sense imo. If a given CPU can clock higher while still maintaining the same IPC, that speaks to a superiority in its architecture. Its pointless to penalize it because it can clock faster.

 

[BTRY B 529th FA BN]

That makes no sense imo. If a given CPU can clock higher while still maintaining the same IPC, that speaks to a superiority in its architecture. Its pointless to penalize it because it can clock faster.

I'm not sure exactly what you are trying to say from what you wrote.

From what I understand comparing IPC is compared the other way around and to do that, I understood that the chips need to be set at the same GHz speed and with no turbo and then measured in benchmarks.

 

[tweakboy]

i5 has no HT ? Am I correct.

I doubt you need HT , but ya a 970 i7 will go toe to toe with current cuz it has 6 cores physical and 6 more logical.. nice

 

[aphelion02]

I'm not sure exactly what you are trying to say from what you wrote.

From what I understand comparing IPC is compared the other way around and to do that, I understood that the chips need to be set at the same GHz speed and with no turbo and then measured in benchmarks.

I don't disagree with that. I'm just trying to say IPC isn't the best way to measure how much 'better' a chip is, which was what the OP was trying to ask.

 

[Arachnotronic]

SNB can clock much higher mostly because it's a 32nm chip rather than a 45nm chip...

 

[bunnyfubbles]

Don't get too caught up in your WEI scores because it is just an incredibly basic rule of thumb scoring system that takes a ton of shortcuts when scoring a system

IIRC, in order to score a 7.9 for CPU you need at least 8 real CPU cores (HT threads don't count), so that 4 core i5 with a score of 7.8 would be scored the same as a 4 core i7 2600K or even a 6 core i7 990x even if both were clocked 1GHz higher than the i5.

That being said, a SandyBridge i5 is pretty much just as fast if not faster than Nehalem i7:

http://www.anandtech.com/bench/Product/363?vs=45 (note how the i5 is actually a slightly slower clock rate)

And of course if we consider overclocking, a 32nm i5 2500K can easily breech 4.4GHz and 4.6-4.8 not too terribly hard to hit. On the flip side 4.4GHz is just about a best case scenario for 45nm i7 with 4-4.2GHz being a more realistic upper end.

 

[aphelion02]

SNB can clock much higher mostly because it's a 32nm chip rather than a 45nm chip...

Process technology is also a very important part of how good the technology is.

 

[Arachnotronic]

Right, but it has very little to do with the CPU architecture itself.

 

[aphelion02]

I think SNB being a tock has unquestionably the superior architecture; and while SNB also has a process advantage, doesn't it have a much smaller die size as well?

 

[Phynaz]

Right, but it has very little to do with the CPU architecture itself.

Ummmm....Incorrect.

Google "speedpath".

 

[bret]

u mad bro?

it only took 10 posts.

 

[Soleron]

Right, but it has very little to do with the CPU architecture itself.

CPUs are designed with the target process in mind, and (at least for Intel and GF's high performance processes) the process is developed with the CPU in mind.

 

[jiffylube1024]

The point I have failed to hear is that clock for clock the are pretty darn close. Take off TURBO and that would be a fair comparison. Run them both at the same clock speed and then to me, we are talkin.

Not sure why you'd do this other than to compare IPC at a fixed clockrate, but remember if you're taking Turbo off of the the Sandy Bridge you should also turn off Hyperthreading on the i7 otherwise you'll be comparing a 4-core system vs a 4 core/8 thread system.

 

[john3850]

I know at the same stock clock the sb is faster.{no oc}
When you oc a sb your only using the Multiplier.
When you oc a i7x58 your your raising your bclk and your L3 which has to increase your score.
I am using 200bclk to match my 1600 ram.
Windows experience gives that 1600 memory a 7.9 score.
Like to see results from a i7x58 200bclk at 4200 and i5 at 4200.
When play Dragon Age II I always see 7 cores at 60% in use now I dont know
how much extra the 3ht cores make but they are being used.