DCS:BS, Affinity and Core i5 / i7 in Turbo

[Panzertard]

TL;DR: I recently discovered some articles from i5 automatic overclocking using 1-2 cores vs 3-4 cores when checking some specs of Core i7 vs Core i5.

Q: "The Return of Affinity hack?"

 

Here's some good reference material if you consider i7 or i5, and wonder if you should HT (minor reference to why it may not boost DCS so much), as well as experimenting with Affinity if you're a Core i7 or i5 owner.

 

Brief overview:

Core i5 vs. Core i7: Differences Between Intel's i5 and i7 Processors

Turbo Mode

Something which will be responsible for a major performance difference is the improvements in turbo mode. The original Core i7 processors came with a turbo mode which allowed the processor to essentially over-clock itself automatically when some cores were not being used. ....

 

Intel has said this will be enhanced with the new Core i5 products as well as with the new Core i7 860 and 870. The Core i5 750, for example, should be able to accelerate from its stock speed of 2.66Ghz to speeds as high as 3.2Ghz. This is a substantial improvement, and it allows new Core i5 processors to perform as well as current Core i7 processors in applications that only use one or two cores. For more in-depth information, read a full review of the

Core i5 performance.

 

Now I havent seen this on my old first generation i7 940 - but I'll be sure to test it out a bit later.

I think have read somewhere that the old i7 9xx may have experienced some difficulties doing this, the boost newer happened, so it may be hard to do with the old versions.

 

The effects of turbo / automatic overclock of i5/i7, Tom's Hardware (oh god I hate the adverts there now);

Intel’s Turbo Boost: Lynnfield Gets Afterburners p.4

 

From the brief look I had it seems

- i5 might perform as good as any i7 if it gets boosted. Goods news.

- i7 owners may actully be able to get some (long lost) more performance?

(If it works on older i7 cpu's)

 

I havent personally tested any of the effects - but if someone else wish to share their experience testing affinity on i7 / i5 - and if you get "Auto Overclock" / "Turbo" mode - then I there's gonna be a lot of people interested in the topic.

 

I'll be back with more material if I have the time to test it myself :)

[Krippz]

Can't wait for the test results.

[Martillo1]

Anyone disabled HT in BIOS (I mean, you see only 4 cores in task manager) and saw performance improvement? If so, how much?

 

P.S.: in i7

[Sarge55]

I did and didn't notice a difference in the FPS. If there was any change it must have been small.

[TAIPAN_]

HT hasn't made a difference for me. I used to leave it off due to recommendations that it's not needed since there are 4 cores anyway. However these recommendations were based on an older chip that HT wasn't so good in.

 

I've got it back on now and it's fine.

 

Regarding 2.66Ghz to speeds as high as 3.2Ghz I've done exactly that with my Core i7.

 

2.66-3.2Ghz overclock with 1600 memory speed was a cinch I didn't change any hardware. I do have a HAF (high airflow) case though that's got a fan in top, side and rear which may help.

 

I like the i7, but if there's a faster i5 one day an upgrade will come.

 

Do you know what socket they are? Will they fit on existing i7 boards or do you need a new motherboard?

[Panzertard]

From the article:

One of the most importance differences between Core i5 and Core i7 is the

use of a new socket, known as LGA1156. This new socket will also be used by some Core i7 products, but current Core i7s use the LGA1366 socket.

[Weta43]

The i5 is a baby i7 - dual channel memory no HT and a locked Hz multiplier.

The i7-860 & i7-870 have higher clock speeds, HT but still dual channel memory & locked Hz multipliers.

All 3 have their own socket "LGA1156" which is smaller than the "LGA1366"

the i-920, i-940 & i-965 all use the larger socket, tripple channel memory, and don't have the frequency multiplier locked.

 

(The 3 new "i" series chips also have a MUCH lower power use than the original "big" i-7's)

 

All the "i" series have built in "turbo" mode which "borrows power from idle cpu cores to overclock active threads".

This is up to +266MHz for the original 9 series, +667MHz for the 5 & 8 series

So for apps running on a single core...

i-7 860 > 2.80GHz + 0.667Ghz = 3.467GHz max for "turbo" mode

i-7 940 > 2.93GHz + 0.266GHz = 3.197GHz max for "turbo" mode

Edited January 6, 2010 by Weta43