**Official e8400/e8500 Retail OC Thread

[Zeus]

With last one was running more then a month @ 1.55-1.57V load volts @ 4400mhz
So i'm sure what to do, and belive it or not there in no degradation, just those chips want to warm up, before get fully stable at it's limits
Right now i remounted my block and look what we've got here
4545@1.42V and only 62-63* load temps Wow



4545@1.42V more than hour Prime 25.6 build6 /x64/ BLEND - more than enough for my needs

Damn, you seem to have a golden hand picking up cpu's!

Very nice one again.

[TEDY]

dstealth i envy you, what coolinig?

[HDCHOPPER]

THKS

[DemonEyez]

With last one was running more then a month @ 1.55-1.57V load volts @ 4400mhz
So i'm sure what to do, and belive it or not there in no degradation, just those chips want to warm up, before get fully stable at it's limits
Right now i remounted my block and look what we've got here
4545@1.42V and only 62-63* load temps Wow



4545@1.42V more than hour Prime 25.6 build6 /x64/ BLEND - more than enough for my needs

Nice chip Can't wait to see a 8 hours prime/Orthos screen

[dark22]

this is some very nice chips...
well done!!!
as it seems all 8xxx can run stable until 60-70 C at full load...
after that no orthos...

[DStealth]

Nice chip Can't wait to see a 8 hours prime/Orthos screen

There is not such an option
I don't have time to wait more than 2 hours and for my needs, that's far beyond stable...
Here is the last screen before, turning off the copmuter and go to work:



Tonight i'll do some more tests, for the moment that's my result 1h30min Blend and stopped @4545mhz 1.42v load ..1.4125 set in Bios
I'm using crappy WC with very weak auto radiator + 2*120mm (70cfm) and MP05SE LE block and also EK8800 GTX Voltmodded in the loop, so any good TR120X can beat it with 2*fans over 70-80cfm

[NINaudio]

From what I understand its another voltage tweak in addition to the CPu Vcore that allows your cpu to draw even more current then your vcore value set in the bios when under heavy load. You can go up to 1v when needed but you also really need extreme cooling to compensate for that nice little feature as things can get scary real fast. IMO it was designed for use when you have Phase or Dice cooling on the Prem to increase stability under serious clocking conditions. The Prem was made for water cooling anyway. Run it low for performance and raise it for high clock stability but make sure you have some serious cooling. Im running my Wolf 8400 in my Mega test Stacker rig which has seperate high flow oversized loops for the CPU and card with multible rads so I can take advantage of that feature without potential issue. Leave it on Auto or at the bottom of the scale.

If it's on Auto, does it stay off? The lowest option for it is 0.70v. That's the last thing I need pumping through my cpu on air!

[CrazyNutz]

Are you saying there's a break in or burn in phase? I was wondering about that. Because both of mine ran better (higher clocks with less voltage) for the first days at lower settings, then after I took them up over 1.4v they needed slightly more vcore at all clocks..

Anything over 1.36v and you run the risk of degrading your CPU, the first one
I got did the same thing, I started off under 1.36v and 3.9ghz all was good
then I got the itch to go higher, and went with 1.41 to get to 4.0ghz all seemed well 6 hours prime stable then left it on over night ran prime the next day and Wham-O!! Not prime stable anymore not even 10 minutes .
So I thought ok I'll just go back to the 3.9ghz and keep it under 1.36v again.
Wrong!!! Now the very best I could do was 3780mhz at 1.36v. So there
you have it.

Also I must add there were few times I had the vcore up to 1.44v (<10mins)
but never >1.45v.

[CrazyNutz]

what should i keep my voltage under on my e8500??

Depends. If you want to minimize the risk of degrading your CPU then keep under 1.36vcore.
If you don't care and are just interested getting some awesome low PI times then go >1.36v, but be prepared to drop some cash on a new CPU.

[mrcape]

Anything over 1.36v and you run the risk of degrading your CPU, the first one
I got did the same thing, I started off under 1.36v and 3.9ghz all was good
then I got the itch to go higher, and went with 1.41 to get to 4.0ghz all seemed well 6 hours prime stable then left it on over night ran prime the next day and Wham-O!! Not prime stable anymore not even 10 minutes .
So I thought ok I'll just go back to the 3.9ghz and keep it under 1.36v again.
Wrong!!! Now the very best I could do was 3780mhz at 1.36v. So there
you have it.

Also I must add there were few times I had the vcore up to 1.44v (<10mins)
but never >1.45v.

Well that's what I was saying in my first post to him warning him not to prime over 1.4v. Like I said I have two chips that seem to have degraded. If you read the whole thread, I've detailed both of mine quite a bit already. But DStealth seems to think it's some sort of phase like a burn in period, and not an indication of damage.

A lot of people are doubting that these could degrade. I'm still not sold either way, but one thing is for sure that the chips don't do what they did at first, high clocks with ultra low voltage. Whether its degradation or a break in is what's of interest to me. I'd like to hope it's the latter as DStealth thinks, because after the initial change mine have been solid. Then again I don't know DStealth or why if and how he's certain about it.

[CrazyNutz]

Well that's what I was saying in my first post to him warning him not to prime over 1.4v. Like I said I have two chips that seem to have degraded. If you read the whole thread, I've detailed both of mine quite a bit already. But DStealth seems to think it's some sort of phase like a burn in period, and not an indication of damage.

A lot of people are doubting that these could degrade. I'm still not sold either way, but one thing is for sure that the chips don't do what they did at first, high clocks with ultra low voltage. Whether its degradation or a break in is what's of interest to me. I'd like to hope it's the latter as DStealth thinks, because after the initial change mine have been solid. Then again I don't know DStealth or why if and how he's certain about it.

Interesting about the burn in. I'll test this theory on my new e8400 that has
never been past 1.33vcore. I will burn it in with prime95, and some video
encodes over the next couple of days, what do you think 48hours worth?


UPDATE: wow, ok this my be too soon but my new e8400 is not 10k prime stable anymore, crapping out in less than 5 minutes.
Seems the DStealth Break in phase theory may hold some water. More testing.....

UPDATE2: Ok, Im seeing something I thought I had see before with my fist e8400. I left my pc off last night to let the TIM cure (per AS5 recommendations)
and note that yesterday I was blend prime stable for 7 hours and then I 10k prime stable for at lest 1 hour before I shut it down.
So today I fired up my pc (and did not run any torture test) and jumped on this thread. I read your reply and started testing
the break/burn-in theory I started with 10k prime and bam rounding error in less than a minute, I then ran it again, rounding error
happened after about 4 minutes, ran it again and still going after 30 minutes.

It seems like it needs to warm up to get stable.

Also I just did a little research on the break-in/burn-in theory, and from what I see it's supposed to make your cpu more stable.

[mrcape]

Let's hope so. Mine seems to have leveled off, meaning now it passes the same stress tests as it did two weeks ago. Of course, it still won't do as well as it did in the beginning.

I still can't help wondering if the benching I did at 1.42v with 545fsb did any damage to it. It was after that night that it needed more juice to be stable at all of my recorded clocks. If it turns out that it is a break in phase, I'll be very glad. Actually, any definitive answer to this change would be great.

[DStealth]

Last try on that Vcore :
4563mhz@1.42V :


There was an error after an hour and some minutes ..it's a pity i didn't catch the right moment
No problem - it was normal, not to be stable with such low Vcore at that speed ...with 24* ambient and crappy WC

[CrazyNutz]

Let's hope so. Mine seems to have leveled off, meaning now it passes the same stress tests as it did two weeks ago. Of course, it still won't do as well as it did in the beginning.

I still can't help wondering if the benching I did at 1.42v with 545fsb did any damage to it. It was after that night that it needed more juice to be stable at all of my recorded clocks. If it turns out that it is a break in phase, I'll be very glad. Actually, any definitive answer to this change would be great.

Well mine is still 10k priming 3 hours so far so good. Im going to shut it down
for about an hour, and start it back up again and run 10k prime to see
if I get the rounding errors again.

[fng77]

To day I orderd a 8400. Hurray. Hoping at a real performance boost from my 2160 at 3,6 Ghz . 1 mb cache to 6 mb he, he. And 45 Nm too, really looking foward to this upgrade

Also seen that 4 Ghz is avalible with most batches. Am I right?

[soundx98]

Should be really easy to hit 4G.
Bios settings and ram timings can make a huge difference in stability.
Go easy on the voltages.

And congratulations!

[ban916]

Just picked up a e8400 at frys for $199 batch q747a258 any luck with this batch?? Also looking for tips on a solid board to get 4.0 on? Thanks guys.

[Furiøùs]

What voltage were you on?

1.425 on eVGA 780i in bios, 1.39v on idle, 1.36-1.37 underload

Well oddly enough i got it stable again at 1780QDR with 1066 on the ram.. Higher then i used to, ram used to be at 800, but i put 0.5 on GTLVREF Lane 0 and now its going strong for 40min so far.. Real wierd. I wish i knew how to tweak these GTLVREF lanes because if so i can probably go so far with this chip.. hmm


GOD DAMNIT speak of the devil it just failed after i finished typing..

[pervi]

is correct a different temp in core 0 and core 1??? (idle)



cooler: XP120 + panaflo 120
mother: ip35pro

[g1raffe]

is correct a different temp in core 0 and core 1??? (idle)

Ouch, 15 degree difference. Difference between the 2 cores is often somewhat different with these Wolfdales, but 15 is one of the worst I have seen. I would try remounting the cooler and re-applying thermal paste, although you may have a faulty sensor in one of the cores, or just a huge difference for some reason which you can't help.

How are the load temps? How much difference between the cores then?

[pervi]

I remounting the cooler and thermal past and the situation does not change.

At full load the difference is 10 degrees.

Can be the XP120 base faulty ?

[unclewebb]

You would rarely if ever see numbers like this with the previous 65nm generation but with 45nm, borked sensors seem more like the norm than the exception.

I did an interesting test where I ran the single threaded version of Prime. I ran it first on core0 of my E8400 with nothing running on core1 and then I did the opposite and ran Prime on core1 with nothing on core0. The difference in temps one way was ~1C and the other way the difference was pretty much zero. Even with a huge difference in load between cores, properly functioning DTS sensors on a 45nm dual core should be outputting almost identical temp data for both cores across the entire operating range. Your processor is out to lunch. Unfortunately, as long as your CPU runs fine at default settings, Intel is not obligated to replace it for sensor issues.

[pervi]

My cpu is not "the one" :S

http://www.ocforums.com/showthread.php?t=546662

[eva2000]

don't worry about differences unless it's causing stability issues

[chispy]

E8400 - Q748A138
VID - 1.1125v
P5K-Deluxe - Bios 0809 - 02/15/08

Max FSB on AIR with TRUE = 560.02










Max OC on AIR with TRUE = 4725.29