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Is this voltage "unsafe"?

889 views 12 replies 9 participants last post by  Gib007 
#1 ·
My temps seem to be within reason still. Just.

I was just messing around to see what I could get with my 955 (I run a 3.8GHz 24/7 OC). But I wanted to see what I could reach.

At 1.7v I got 4.6GHz. Not quite sure if I could get the clock higher (I just messed with multiplier, no HT changes). Seems to run stable, but 1.7v o_O; Little high maybe?
 
#4 ·
It's not so much the voltage but high temps that kills the CPU...to a point. I wouldn't crank it to 2v or anything LOL. But as long as you don't put load on the CPU you should be OK. I'd imagine with that voltage and OC you were probably idling at 55-60c even with the H50.

Sounds like you have a pretty good clocker on your hands though. I used to have a C2 and it would not get 4ghz stable no matter what on air cooling, I tried up to 1.65v. I could boot and get a validation, but any load at all and BSOD.
 
#6 ·
Quote:


Originally Posted by Gib007
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Wow, that's a tremendous voltage. Definitely don't run that 24/7!
Stick to around 1.5500V maximum and whatever overclock you can get out of that. That's a decent 24/7. I run mine at 3.9GHz with 1.5125V, for example.

It's really weird how my CPU is working.

I got my CPU to work at 3.80GHz @ 1.4125v with prime95 for 30 minutes (I was impatient and wanted to do other things so I stopped it after that).

So I'm running it 24/7 at 3.8GHz @ 1.425v (just incase if there's an off-chance of instability at 1.4125). The voltage decrease from 1.45v has decreased my max temps by 1 to 1.5 degrees celcius.

But after 3.9GHz, I seem to have to crank the voltage harshly. While the temps don't rise too much compared to how much voltage I have to put in. I need 1.55v for just over 4.1GHz... and then to reach 4.2GHz I need more than 1.55v (about 1.575)... and then it keeps going up. This is all multiplier, no HT changes.
 
#8 ·
Quote:


Originally Posted by PaulWog
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It's really weird how my CPU is working.

I got my CPU to work at 3.80GHz @ 1.4125v with prime95 for 30 minutes (I was impatient and wanted to do other things so I stopped it after that).

So I'm running it 24/7 at 3.8GHz @ 1.425v (just incase if there's an off-chance of instability at 1.4125). The voltage decrease from 1.45v has decreased my max temps by 1 to 1.5 degrees celcius.

But after 3.9GHz, I seem to have to crank the voltage harshly. While the temps don't rise too much compared to how much voltage I have to put in. I need 1.55v for just over 4.1GHz... and then to reach 4.2GHz I need more than 1.55v (about 1.575)... and then it keeps going up. This is all multiplier, no HT changes.

Good work on using the CPU multiplier alone, this way you know that the CPU is what's unstable if you get a crash/error. It's the best way really.

That sounds about right too. 1.4125V for 3.8GHz is good, and so is 1.4250V for the extra margin of stability, especially since your temperatures must be good here. For reference, I can run mine at stock 3.4GHz, 3.5GHz, 3.6GHz and 3.7GHz on 1.3875V (just below stock 1.4000V). For 3.8GHz I need 1.4625V and for 3.9GHz I need 1.5125V, which is what I'm at now. I haven't really tried to push for 4.0GHz for fear of needing more than 1.5500V, which I don't want to set. In either case, it won't make any performance difference.

What voltages do you need for 3.9GHz and 4.0GHz to be stable?
Perhaps you can keep those 24/7 as long as the voltage isn't above 1.5500V and the temperatures are good. If you can have 4.1GHz stable with 1.5500V, it sounds to me as if 4.0GHz will need a bit below that, which is great. I say go for it if temperatures allow!

As a guideline, try to keep your full load temperature to a maximum of 55°C, no matter what.

That said, any thoughts on overclocking your CPU/NB too?

Once you're happy with your CPU overclock, set it back to stock and start cranking up the CPU/NB!

I've got mine at 2600MHz (from the default 2000MHz) with 1.3000V (1.1000V is the stock). Works great and provides a nice performance boost. You might even be able to get 2800MHz out of it. For this one, try to keep to a maximum of 1.4000V for the CPU/NB voltage and don't touch the NB voltage (you don't need to). Make sure you have good case cooling and that your Northbridge motherboard chipset has a heatsink at least!


EDIT: You don't tell us what motherboard model it is you have on your signature computer. From the details you entered, I'm going to assume it's mine - Asus M4A79XTD EVO. In that case, it's a good motherboard with nice chipset cooling so as long as you have decent case cooling, go for that 2600MHz CPU/NB with 1.3000V and test it out. Then you can try for 2800MHz if you want but 2600MHz is more than enough for a good boost. Once you're happy, overclock your CPU too and have both overclocks running - test for stability again just in case!
 
#9 ·
Quote:


Originally Posted by Gib007
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What voltages do you need for 3.9GHz and 4.0GHz to be stable?
Perhaps you can keep those 24/7 as long as the voltage isn't above 1.5500V and the temperatures are good. If you can have 4.1GHz stable with 1.5500V, it sounds to me as if 4.0GHz will need a bit below that, which is great. I say go for it if temperatures allow!

As a guideline, try to keep your full load temperature to a maximum of 55°C, no matter what.

That said, any thoughts on overclocking your CPU/NB too?


Thanks :-D +rep. Good advice.

Yeh I can get 4.10GHz @ 1.55v, though I haven't tested it overnight for a real stability check. I know I can run 4.00GHz stable at 1.5v or maybe 1.5125v at worst (once again, haven't quite tested it extensively). I'm liking my 3.8GHz @ 1.425v right now :-D (it's really cool, right now I'm idling at 26 Celcius, temps have gone down to 24 Celcius at lowest, and I don't see load over 39 Celcius using prime95... but this isn't summertime yet).

My CPU/NB is overclocked to 2400MHz @ 1.2125v currently. I know so little about CPU/NB OC'ing.

When this comp is old enough (2 years or more), I'll either consider selling it... or upping the OC to a 24/7 clock of 4.6GHz or something
with a CPU/NB of 2800MHz. See how long it lasts.
 
#12 ·
Quote:


Originally Posted by FREELINE57
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1.7 just to get some validation, naw...it won't hurt the chip! Although, i'm curious if you could get more.

The validation is not valid on yours....... See the red "X" on it. I would love to see proof on the OP's validation.
 
#13 ·
Quote:


Originally Posted by PaulWog
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Thanks :-D +rep. Good advice.

Yeh I can get 4.10GHz @ 1.55v, though I haven't tested it overnight for a real stability check. I know I can run 4.00GHz stable at 1.5v or maybe 1.5125v at worst (once again, haven't quite tested it extensively). I'm liking my 3.8GHz @ 1.425v right now :-D (it's really cool, right now I'm idling at 26 Celcius, temps have gone down to 24 Celcius at lowest, and I don't see load over 39 Celcius using prime95... but this isn't summertime yet).

My CPU/NB is overclocked to 2400MHz @ 1.2125v currently. I know so little about CPU/NB OC'ing.

When this comp is old enough (2 years or more), I'll either consider selling it... or upping the OC to a 24/7 clock of 4.6GHz or something
with a CPU/NB of 2800MHz. See how long it lasts.

Hehe, thank you, and no problem!

4.1GHz at 1.5500V sounds decent enough but personally I'd stick to 1.5000V/1.5125V for 4.0GHz for 24.7 and be very happy with it. Your full load temperature of 39°C for 3.8GHz at 1.4250V sounds great and is definitely asking for more overclocking!

Even if you full load at 55°C on 4.0GHz (which you definitely won't), it's still great. Put it this way, you won't see any difference in performance with your temperature being lower but you will see some difference in performance from your clock speed being higher. On that note - overclock more!


CPU/NB at 2400MHz with 1.2125V is good. Go for 2600MHz. I can run mine at that with 1.3000V and it's perfectly stable. That's still 0.1000V leeway for more so it's great.
 
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