Question about i7 8 threads?

userpasswordpassport · 03-22-2010, 11:57 PM #1

hi, i have some questions about how this CPU works in dolphin, i saw some videos in youtube, playing mario kart wii and other wii games on a laptop widh intel i7 processor, running everything full speed very easy, im reallly impressed, but my question is about the threads.
the intel core i7 runs better because runs 8 threads? or only because speed or anything else?

i was thinking about dolphin use Dual core to run games, but if 2 cores have 4 threads is to compare to emulate dolphin with 4 cores?

i want to know if you run 4 threads for dolphin, or only 2.
please answer, and sorry to bother Tongue

**NaturalViolence** · (This post was last modified: 03-23-2010, 07:10 AM by NaturalViolence.)

2 threads, period. Just because a core has 2 threads does not mean it has to use both of them, in the same way that a multicore cpu does not have to use all of it's cores. Applications are designed to use a specific number of threads for a task, HT allows you to design apps that divide work into more threads than the number of cores you have, but if the applications is not setup to use that many threads the cpu will simply give each thread its own core. Dolphin is setup to use 2 threads therefore the cpu will use 1 thread per core on 2 cores, get it?

**Ocean** · 03-23-2010, 06:16 PM #3

I tried on both 8 and 4 threads (switch off/on HT in bios) and didn't notice any speed difference at all. All games were already at full fps on either option, so if you want the cpu to use a bit less wattage, just turn off hyperthreading while playing dolphin. It really doesn't matter.

xRyudo · 03-23-2010, 07:02 PM #4

(03-23-2010, 06:16 PM)Ocean Wrote: I tried on both 8 and 4 threads (switch off/on HT in bios) and didn't notice any speed difference at all. All games were already at full fps on either option, so if you want the cpu to use a bit less wattage, just turn off hyperthreading while playing dolphin. It really doesn't matter.

^This.

I turned my HT off for now to reduce temperatures, because I was getting into 90s while playing Dolphin. Now I barely break 70 with HT off and games still run at full speed.

GundamQuatro · 03-23-2010, 11:09 PM #5

(03-23-2010, 07:02 PM)xRyudo Wrote:
(03-23-2010, 06:16 PM)Ocean Wrote: I tried on both 8 and 4 threads (switch off/on HT in bios) and didn't notice any speed difference at all. All games were already at full fps on either option, so if you want the cpu to use a bit less wattage, just turn off hyperthreading while playing dolphin. It really doesn't matter.
^This.

I turned my HT off for now to reduce temperatures, because I was getting into 90s while playing Dolphin. Now I barely break 70 with HT off and games still run at full speed.

70c????? oh damn i rarely go over the 50s Tongue

CacoFFF · 03-24-2010, 08:04 AM #6

I had no idea i7's HT made temperature skyrocket, even when only using dual-tri core apps like Dolphin.
I think disabling hyperthreading on a i7 helps when you have 'Lock threads to cores' enabled in Dolphin.

Makes me think now, disabling hyperthreading, enabling thread lock, wouldn't that keep the entire cpu even at less temperatures? I'm guessing that 2 fully operating cores heat less than 4 partial ones.

Anyone willing to test and post?

xRyudo · (This post was last modified: 03-24-2010, 11:32 AM by xRyudo.)

Quote:I think disabling hyperthreading on a i7 helps when you have 'Lock threads to cores' enabled in Dolphin.

Locking threads makes it slower. It binds it to 1 core. Useless function for an i7 and bad for playing games.

Me and some other people actually talked about this on IRC the other day, and everyone said the same thing that it slowed everything down for them.

(03-23-2010, 11:09 PM)GundamQuatro Wrote: 70c????? oh damn i rarely go over the 50s

You can't compare the temperatures of an Athlon X2 with an i7. The i7 is notorious for getting hot.

**NaturalViolence** · (This post was last modified: 03-24-2010, 02:12 PM by NaturalViolence.)

Quote:You can't compare the temperatures of an Athlon X2 with an i7. The i7 is notorious for getting hot.

Also keep in mind that an I7 can tolerate much higher temperatures. Core2duo wolfdale can get up to 65 celcius while still being "safe" according to intel, meaning almost no loss of lifespan, and can function at up to 85 celcius with a loss of lifespan. Of course these numbers vary slightly from one individual cpu to another but those are the temps that intel provided which must therefore represent a minimum. For the I7 both of those numbers are about 20 degrees higher, 85 for "safe", and 100 for "functional". I can't say for sure but from what I understand I think it has something to do with the transistors being placed further apart from each other. I refused to believe this at first since it went against my past experiences (I had never in my wildest dreams thought a cpu could function at a temperature that high, I thought that it was impossible) but then my friend got a 920 and I ran some tests on it and the numbers are accurate. In fact in a poorly ventilated case the 920 did actually get up to about 83 celcius at full load on stock cooling and stock settings, and it was fine. Also keep in mind that raising the voltage will lower the maximum tolerable temperature. To test intels claims I overclocked it and got it up to 97 at full load, still was prime 95 stable (of course I reverted this after the test for obvious reasons, don't want to shorten the lifespan from heat damage). For those of you with the patience or interest to read this, thanks.

GodRays · 03-24-2010, 02:22 PM #9

Cool story, bro. Also, i really dig your signature, put more stuff in it plz.

**NaturalViolence** · 03-24-2010, 02:28 PM **#10**

Quote:Also, i really dig your signature, put more stuff in it plz.

Lol. It's kind of an inside joke that started with a friend of mine. You have to try and reach the max number of allowed characters with only specs (my original was 4x that long but I had to keep trimming it till the character count was low enough).