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Is your CPU stable on OCCT's Linpack @ Max setting?

^ what he said. VTT needs to be balanced properly, and not just raised for no reason.
 
^ what he said. VTT needs to be balanced properly, and not just raised for no reason.

Exactly VTT is a voltage that MANY other voltages and skews are derrived (SP?) from, and if its even a little bit out it can really bugger your system.
 
Geez, you make it seem like messing with voltage is like trying to disable a nuclear bomb... I ran 1.5v through my 5200+ and it didn't care. Then again with 1.375v through a Phenom 9500 blew up my motherboard, cpu and graphics card... but vcore was the only thing I touched.
 
Geez, you make it seem like messing with voltage is like trying to disable a nuclear bomb... I ran 1.5v through my 5200+ and it didn't care. Then again with 1.375v through a Phenom 9500 blew up my motherboard, cpu and graphics card... but vcore was the only thing I touched.

VTT voltage on intel is supposed to be a percentage of Vcore. too low and you get unstable, too high and you damage the chip. i cant remember off the top of my head (i'm new to 45nm) but i think its supposed to be 67% of Vcore.

I know on my mobo my stock voltage is 1.236 (low, its a xeon) and my stock VTT was 1.100V (lowest it goes on this board). That comes out to about 75%. If i had a higher stock voltage chip it'd be in the sweet spot at stock, and since its not i get some OC's without having to change VTT.
 
775 Core based degredation is all based on VTT/PLL/GTT voltages being out of wack. NOT heat related. Considering that MOST 45nm start to throttle at 100*C, now also assuming that there is lets say a 40% fudge factor here over say 4-8 seconds. (What most ICs use for example, and still applies to CPUs) you would need to hold your 45nm CPU w/ tjmax100 @ ~130*C for 4-8 seconds to cause perminant damage. and considering how FAST the throttling actually kicks in you would be lucky to break 110, and definitly not for more than 4 seconds.

I have run plenty of CPUs are VERY high temps without any degredation, but the moment you load them with the wrong voltage/settings you can cause instant degredation. the socket939 AMDs were VERY bad for this (first onchip memory controllers) if you were even slightly off you would cause memorycontroller degredation nearly instantly.

Agree 100%.

I've run an e2160 with No HSF on it at all, just the bare chip... I couldn't get it to budge over 105c.
Admitedly I had dropped the voltage for the test, but the chip was working at over 100c for over 30 mins with no ill-effects.

Temperature isn't a problem, even for the 45nm chips. It's voltage that will cause degredation.

Edit: I also forgot to connect the pump when I had my Watercooling stuff... my e6400 was at 100c for 24 hours before i figured out why everything was stuttery!
That CPU still continues to be a good overclocker to this day!
 
VTT voltage on intel is supposed to be a percentage of Vcore. too low and you get unstable, too high and you damage the chip. i cant remember off the top of my head (i'm new to 45nm) but i think its supposed to be 67% of Vcore.

I know on my mobo my stock voltage is 1.236 (low, its a xeon) and my stock VTT was 1.100V (lowest it goes on this board). That comes out to about 75%. If i had a higher stock voltage chip it'd be in the sweet spot at stock, and since its not i get some OC's without having to change VTT.

Like with anything overclocking is not covered by Intel's specs. VTT from what I hear is acctually supposed to be higher than VCC but that is allways up for debate. I usually set my VTT alittle lower than my VCC at load. I think that the reason for this is voltage spikes. Anyways I hear having your VTT too low can acctually be worse for your chip. We are talking 775 here, btw. I don't know muck about 1366. But most importantly your cpuGTL ref and nbGTL ref is based off of your VTT. I think Intel spec is 67%, thats probably where you are getting that number from. Having your GTLs off 3% can mean the difference between failing prime in under an hour and being 24 hour stable but changeing your VCC, VTT, or FBS can throw this off. You generally want to keep your GTL voltage between 0.80v and 1.0v.

These are two of my favorite threads about VTT on a 775.

Wolfdale VTT game (This ones a classic)

Everything you need to know about GTLs on a 775. (This is a great read)
 
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yeah i probably got GTL mixed in there. i only just upped to an x48 and a 45nm, didnt have these options on my last board.
 
since when has intel rated that? whoever told you that, made it up. ever heard of TJmax? that is the max temp for your chip, at which it throttles. heat DOES NOT kill intel chips, by design. (it can make them unstable, but it WONT damage them)



you're mistaking intel burn tests use of linpack for OCCT's use of linpack :) the OCCT one uses a lot more ram and therefore the NB as well. its a far better test.

They both use all available ram and I did run OCCT as well, just not as long of a run. I have never noticed a difference between my temps or load (wattage) between the two. What exactly is the difference between the programs?

He said it failed the Prime small fft test which takes next to no ram at all

This was on my Wolfdale and 4gb of ram on several versions of IBT. You can run a custom prime run with all of your available ram (I know of a couple of good settings) and a small fft run that will acctually pick up errors that Linpack wont. At the end of the day, Linpack stable dosen't mean 100% stability or even prime stable.
 
Like with anything overclocking is not covered by Intel's specs. VTT from what I hear is acctually supposed to be higher than VCC but that is allways up for debate. I usually set my VTT alittle lower than my VCC at load. I think that the reason for this is voltage spikes. Anyways I hear having your VTT too low can acctually be worse for your chip. We are talking 775 here, btw. I don't know muck about 1366. But most importantly your cpuGTL ref and nbGTL ref is based off of your VTT. I think Intel spec is 67%, thats probably where you are getting that number from. Having your GTLs off 3% can mean the difference between failing prime in under an hour and being 24 hour stable but changeing your VCC, VTT, or FBS can throw this off. You generally want to keep your GTL voltage between 0.80v and 1.0v.

These are two of my favorite threads about VTT on a 775.

Wolfdale VTT game (This ones a classic)

Everything you need to know about GTLs on a 775. (This is a great read)

yeah i probably got GTL mixed in there. i only just upped to an x48 and a 45nm, didnt have these options on my last board.


VTT (vFSB) and GTLs are percentages, I wrote a few giant posts on theses a few months back when we had the influx of "HOW DO I OVERCLOCK MY 45nm??!?!" but most people seemed to ignore it.....
 
VTT (vFSB) and GTLs are percentages, I wrote a few giant posts on theses a few months back when we had the influx of "HOW DO I OVERCLOCK MY 45nm??!?!" but most people seemed to ignore it.....

Neither one is a percentage. On my P5Q my GTL is a percentage but on my old 780i I could acctually input the actual GTL voltage, I belive that you can do the same on the UD3P/R and a few others. Read through the second link that I posted. Its not overly technical but really helped me to understand how my GTLs effect my processor while overclocking.

@Mussels - I sold my Biostar Tpower within the week that I bought it mostly because you cant really adjust the GTLs. Which board are you using?
 
Neither one is a percentage. On my P5Q my GTL is a percentage but on my old 780i I could acctually input the actual GTL voltage, I belive that you can do the same on the UD3P/R and a few others. Read through the second link that I posted. Its not overly technical but really helped me to understand how my GTLs effect my processor while overclocking.

@Mussels - I sold my Biostar Tpower within the week that I bought it mostly because you cant really adjust the GTLs. Which board are you using?

Sorry not what i meant in the above post.

What your VTT/GTLS adjust is based off a percentage of them (VFSB Target) most boards (save for the x48(that i have used) you are setting the voltage offset in a percentage (0.630 percent of whatever VTT is set to) on the x48 you can adjust it in milivolts IIRC.

So essentially its all ratio/percentages ;)
 
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