Why does Prime95 overstress my system?

[The Chicagoan]

So I go ahead and run prime95 to see if my overclock is stable with my new cooler I just got. And the as soon as I run it the temps go to 100C+ instantly. I even had a weak overclock done, 4.2 GHz 1.29 volts. 100C+ now with that overclock set I was getting 20-25C idle, and in most games I was getting around 40-50C. AIDA64 was around 70C. Currently right now my overclock is at 4.8 GHz with a core voltage of 1.40 on my i7 4790K and it instantly goes super high in temp to over 100C, but idle my temps are at 25-30C.

My cooler is a Corsair Hydro 150i Pro RGB 360MM I even had the pump speed maxed and fan speed maxed same thing. So why does prime95 do that?

[Vulkan]

Which version of prime95 are you using ?

[🍃🪻🪷Sylvie🩵🍸🍵]

Originally posted by The Chicagoan:

So I go ahead and run prime95 to see if my overclock is stable with my new cooler I just got. And the as soon as I run it the temps go to 100C+ instantly. I even had a weak overclock done, 4.2 GHz 1.29 volts. 100C+ now with that overclock set I was getting 20-25C idle, and in most games I was getting around 40-50C. AIDA64 was around 70C. Currently right now my overclock is at 4.8 GHz with a core voltage of 1.40 on my i7 4790K and it instantly goes super high in temp to over 100C, but idle my temps are at 25-30C.

My cooler is a Corsair Hydro 150i Pro RGB 360MM I even had the pump speed maxed and fan speed maxed same thing. So why does prime95 do that?

The reason why temp is too high when running Prime95 is because you may have set improper overclocking settings via BIOS. Perhaps, LLC is too high, improper fan curve, etc. But still, it's not recommended to run Prime95 test since it applies way too much voltage on your CPU, and thus this generates more heat and will also drastically lower CPU lifespan.

[The Chicagoan]

Originally posted by SavageSoutherner:

Which version of prime95 are you using ?

the newest one that was avalible on their website.

[Malygos]

Because prime hammers avx work loads you can download 26.6 it doesnt have that but if it cant pass an avx stress its not stable

[Vulkan]

Originally posted by The Chicagoan:

Originally posted by SavageSoutherner:

Which version of prime95 are you using ?

the newest one that was avalible on their website.

That would be why then as the newer versions hammers the CPU as it uses avx workloads . Use 26.6. personally I would use realbench to stress your CPU it's very reliable and good at catching any instability. Good luck man

[The Chicagoan]

Originally posted by MancSoulja:

Originally posted by SavageSoutherner:

That would be why then as the newer versions hammers the CPU as it uses avx workloads . Use 26.6. personally I would use realbench to stress your CPU it's very reliable and good at catching any instability. Good luck man

'Hammering' the CPU as you put it is the purpose of a stress test. You can't overstress a CPU, it can only do what it is designed to do, and if it can't do that, it isn't stable.

But it is stable, so far since I didn't blue screen or freeze when it bit 100c, but for if to go that hot on almost any voltage I choose, low or high is very odd. Even at stock it goes to almost 80c to 90c...

[Malygos]

And you’re thermal throttling at those temps use intels extreme tuning see if it hits those temps it tells you when its throttling from heat i generally get it around 85-90c my rule of thumb is back off 100mhz when its too hot that extra 1-2% isnt gonna matter in games and it usually lowers the temps due to lower voltage.

[Vulkan]

Not surprised you deleted your post mac soulja you sound like an idiot. Hammering , stressing same thing I just chose different wording. Prime95 puts unnecessary workloads on your CPU that no other program /game will realistically use that's why it's called a torture test. Personally I would use realbench or 3dmark timespy . Try 26.6 and report back mate

[Overseer]

Did you try a different cooler? It could be clogged and barely work.

Also which prime95 test are we talking about?

[Supafly]

Highest version of Prime you should use for a 4790k is Prime v26.6 as higher versions using AVX majorly overstress it. If you want to use a newer version of Prime change your Bios settings so AVX clock is set 100-200mhz lower than your main CPU clock....maybe more. That way all AVX instructions won't hit the same speed and crank up your temps whilst the none AVX instructions will allowing CPU to hit the speeds you're testing.

Just using Prime v26.6 is the simplest and best way to stress test a 4790k using Prime.

[sawdust3d]

OP, did you just install that new cooler?

It's worth checking the it is actually seated properly.

[tacoshy]

Originally posted by Sammy:

Originally posted by The Chicagoan:

The reason why temp is too high when running Prime95 is because you may have set improper overclocking settings via BIOS. Perhaps, LLC is too high, improper fan curve, etc. But still, it's not recommended to run Prime95 test since it applies way too much voltage on your CPU, and thus this generates more heat and will also drastically lower CPU lifespan.

LLC does not really cause an icnrease in temperature for the CPU. The VRM might get hotter but not the CPU.
Prime 95 does not increase the volatage of the CPU. Espacially not when overclockign right -> fixed voltage.

The problem morelike is a non-delidded CPU + 1.40V the OP applying. As matter of fact I used Prime 95 v26.6 on a delidded 7700K @1.465V and merely reached into 80C on a 280mm AIO.

Originally posted by Suicidal Monkey:

Highest version of Prime you should use for a 4790k is Prime v26.6 as higher versions using AVX majorly overstress it. If you want to use a newer version of Prime change your Bios settings so AVX clock is set 100-200mhz lower than your main CPU clock....maybe more. That way all AVX instructions won't hit the same speed and crank up your temps whilst the none AVX instructions will allowing CPU to hit the speeds you're testing.

Just using Prime v26.6 is the simplest and best way to stress test a 4790k using Prime.

yes correct. besides that v26.6 is the msot effective one. newer evrsion often pass a etst while in gaming or in v26.6 it does not.
Good advice on the AVX offset most new ppl ignoring when overclocking.