Corsair H75 i5 4670k - Prime95

Drake5

Drake5

Drake5

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I got a Corsair H75 earlier so I installed it and OC'd to 4Ghz, in prime after about 10 mins I was getting temps close to 100C so I took off the H75 and put it back on with new paste.

I'm OC'd to 4GHz again now and after 10 mins in prime I'm hitting around 80C, does this sound about right?

Idle temp seems to be about 30-32c

Cheers
 
Does not sound right at all unless your ambients are way high. How's the TIM spread looking?

Then again, I'd never recommend using Prime95 anyway. Mind giving something like Asus Realbench or Aida64 stability test a whirl?
 
Just ran Realbench 2 for 15 minutes and max temp was 62C.

Also earlier on when I was running Prime95 I was getting some weird 'hardware error' but I suspect that was something to do with the voltage on my OC as I was crashing as well but since upping it I haven't crashed since.

I read that Prime95 can cause i5 4670k to go really hot

Not sure why realbench is a fine temp but Prime95 isn't
 
Just ran Prime95 again which was fine temp wise but it stopped about 5 minutes and with 'FATAL ERROR' Hardware failure detected.
 
Prime uses Avx instructions which are a lot more demanding than real bench and force the more voltage to the cpu(upto 0.1v),increasing the temps further.

What are your current bios settings for your cpu? and what Vcore do you see in windows under load?
 
I've just gone back to full stock and Prime95 is fine now, no more errors and temps seem good. At the start of Prime95 temps seem to be around 75c but drop to around 62c.

I do want to overclock to about 4.2GHz but I haven't overclocked for a while and I've pretty much forgot what settings I had last time.

Someone with the exact same board and CPU as me recommended these settings

Steps taken (in a nutshell):
In BIOS-
1.Set Core Ratio to "Dynamic" Mode
2.Set Both Core and Cache (Ring) Voltage Modes to "Adaptive"
3.Core Multiplier:43x
4.Core Voltage:1.18V
5.Processor Cache (Ring) Ratio:42x
6.Processor Cache (Ring) Voltage:1.155V
 
Tom_D said:
I've just gone back to full stock and Prime95 is fine now, no more errors and temps seem good. At the start of Prime95 temps seem to be around 75c but drop to around 62c.

I do want to overclock to about 4.2GHz but I haven't overclocked for a while and I've pretty much forgot what settings I had last time.

Someone with the exact same board and CPU as me recommended these settings

Steps taken (in a nutshell):
In BIOS-
1.Set Core Ratio to "Dynamic" Mode
2.Set Both Core and Cache (Ring) Voltage Modes to "Adaptive"
3.Core Multiplier:43x
4.Core Voltage:1.18V
5.Processor Cache (Ring) Ratio:42x
6.Processor Cache (Ring) Voltage:1.155V
Click to expand...
Yea this wasnt very sound advice ^^ You should be able to get around 4.4ghz unless you got a real bad clocker

When overclocking on haswell you REALLY dont want adaptive voltages,your asking for trouble using them.

In realbench at stock what vcore does it show in hwmonitor?
 
Tom_D said:
So what does that mean exactly?

Mobo is Z87-G43
Click to expand...


CPU's arnt born equal. For instance, not every 4670k owners cpu require the same VID(Vcore) to achieve its stock speeds.This varies from around 1.0v('good') upto around 1.2v(bad).An increace to vcore is the main reason why cpus get hotter as you overclock them.So a chip with lower VID at stock speeds is generally considered better as it will run cooler at stock speeds due to lower vcore requirements,and thus has more headroom for OCing(theoretically)
 
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MrMD said:
CPU's arnt born equal. For instance, not every 4670k owners cpu require the same VID(Vcore) to achieve its stock speeds.This varies from around 1.0v('good') upto around 1.2v(bad).An increace to vcore is the main reason why cpus get hotter as you overclock them.So a chip with lower VID at stock speeds is generally considered better as it will run cooler at stock speeds due to lower vcore requirements,and thus has more headroom for OCing(theoretically)
Click to expand...

So my CPU isn't faulty for being at 1.2v when under load at stock?

I did have this CPU at 4.2GHz before stable but I can't remember the settings I used. I know voltage was around 1.6v.

I want to get back to 4.2GHz again

No idea where to start though
 
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Tom_D said:
So my CPU isn't faulty for being at 1.2v when under load at stock?

I did have this CPU at 4.2GHz before stable but I can't remember the settings I used. I know voltage was around 1.6v.
Click to expand...

1.2v under load at stock isnt unheard of,although its pretty rare to be that high.

I'd defiantly recheck the bios settings to make sure you didnt miss a setting somewhere ,maybe even loading optimized defaults in the bios to make sure.

Nah you wont have been at 1.6vcore,if so you cpu would have melted :eek:
Its not really safe to go over 1.35v vcore on these cpu's unless you have custom watercooling ( or no fear :D)

Could try this
Multi 42x
vcore 1.250
Cache ratio 40x at 1.20v cache voltage(vring)
input voltage (Vrin 1.900v)
 
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MrMD said:
1.2v under load at stock isnt unheard of,although its pretty rare to be that high.

I'd defiantly recheck the bios settings to make sure you didnt miss a setting somewhere ,maybe even loading optimized defaults in the bios to make sure.

Nah you wont have been at 1.6vcore,if so you cpu would have melted :eek:
Its not really safe to go over 1.35v vcore on these cpu's unless you have custom watercooling ( or no fear :D)
Click to expand...

I did reset the bios and it was still 1.2V under load yeah.

I meant I had vcore at 1.16v :) It was stable at that at 4.2Ghz
 
Tom_D said:
I did reset the bios and it was still 1.2V under load yeah.

I meant I had vcore at 1.16v :) It was stable at that at 4.2Ghz
Click to expand...


If thats the case, im not sure then :confused:
No reason why you should be stable before hand at significantly lower voltages and not anymore.

Do you have high speed ram with XMP profiles enabled?
 
My RAM is just 1600MHz with XMP enabled

I've just tried to OC to 4.2GHz but getting hardware failures in Prime95 almost instantly. Voltage is at 1.165 and ring voltage is at 1.150. Should I keep increasing them until it becomes stable?
 
Tom_D said:
My RAM is just 1600MHz with XMP enabled

I've just tried to OC to 4.2GHz but getting hardware failures in Prime95 almost instantly. Voltage is at 1.165 and ring voltage is at 1.150. Should I keep increasing them until it becomes stable?
Click to expand...

For now eliminate the cache from the equation completey,and set it to 35x at auto ring voltage.(you can clock it after you get the cores stable).Also disable the rams xmp and run it at 1333mhz(re-enable after you get stability)


For now focus on the Multiplier and vcore.
First get 40x stable.
Then up the multi to 42x and and increace vcore in small increments till you get stability.
 
Multiplyer is at 42, ring ratio is at 35 with auto voltage. XMP is disabled and RAM is running at 1333Mhz.

I have CPU voltage at 1.18 but still locking up within a couple minutes on prime95. Continue to up the voltage?
 
Yes, you'lll just have to keep going until you get stable.

Are you on latest bios? HAve you checked pump rpm is as it should be?
 
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