Worth it going from 4.0GHz to 4.9GHz?

[theonerm2]

I bought a 4790K that can supposedly overclock to 4.9GHz at 1.35v and 1.28v for 4.8GHz. It's delidded already so I don't need to worry about delidding. I paid $240. The PCB has a slight bend to it. Not enough to hurt anything. It was sold as is for parts because of the bend. I have a 4770K that can only reliably overclock to 4GHz. So this nets me a good 22.5% boost in clock speed. Was it worth it though? I think so. I enjoy overclocking. The 4770K not being able to go beyond 4GHz would keep me up at night sometimes. I'd be thinking about how disappointed I was with the overclock. I think I'll be much more satisfied with this 4790K. I used to think... If only I could reach 4.5GHz I'd be happy. Now I can go beyond that. Before the 4770K I had a 4690K that could do 4.6GHz. I used to think I messed up by going with the 4770K since I lost out on a good 600MHz. I like to play games and I'm starting to get into making youtube videos. It might not help much with games but it will certainly help with video editing. Oh and I wonder how the 4790K at 4.9GHz does against a 7700K?

 

[WildCard999]

What is the voltage & cooler your using with the 4770K? I was able to get a stable 4.4ghz @1.250V with a Corsair H100i, no delid.

Although I will say I've since reverted my OC back to stock since all I really do is game and the OC really made no difference over the stock/boost clocks and having the higher temps during the summer isn't worth it (IMO). The temp difference was about 15C between stock & OC load.

As for the difference between the 4790K & 7700K here's some benchmarks (stock clocks).
http://cpu.userbenchmark.com/Compare/Intel-Core-i7-7700K-vs-Intel-Core-i7-4790K/3647vs2384
With the higher OC it would probably close the performance gap a bit.

 

[iamacow]

98% of those do not go above 4.5ghz without some crazy voltage (or at all), so consider yourself lucky if you get 1.3v for 4.8ghz. That is a dream chip.

i7 4790k with 2400 Ram is very close to an stock i7-7700K in most games. However once you start to use slower memory like 1600 than the 7700k pulls waaaay ahead.

 

[Eximo]

There is little difference in the output of a Haswell vs Skylake/Kabylake.

I ran a bench just before disassembly of my i7-4770k @ 4.3Ghz, the i7-7700k even at 5Ghz only pulled ahead by about 20%, certainly mostly the clockspeed difference. So at 4.9Ghz it will be very close indeed. I recall from very early benchmarks that the i7-4790k was even faster in some applications, though that was early BIOS and motherboards/drivers.

The Kabylake series has the usual minor improvements, and some added technology, but brute force computation only improves by as little as 5-10% per generation. Kabylake is effectively Skylake with higher clocks.

I would probably run the 4.8Ghz at 1.28. 1.35 is what my 4770k maxed out at, and the temperatures were crazy. It will probably last a lot longer at 1.28.

 

[theonerm2]

What is the voltage & cooler your using with the 4770K? I was able to get a stable 4.4ghz @1.250V with a Corsair H100i, no delid.

Although I will say I've since reverted my OC back to stock since all I really do is game and the OC really made no difference over the stock/boost clocks and having the higher temps during the summer isn't worth it (IMO). The temp difference was about 15C between stock & OC load.

As for the difference between the 4790K & 7700K here's some benchmarks (stock clocks).
http://cpu.userbenchmark.com/Compare/Intel-Core-i7-7700K-vs-Intel-Core-i7-4790K/3647vs2384
With the higher OC it would probably close the performance gap a bit.

I use auto voltage and an H105 cooler to reach 4GHz. I can get a semi stable 4.2GHz at 1.35v. It's really a dud as far as overclocking goes. I got temps in the 70's and low 80's with occt running at 1.35v. My 4770K has been delidded to improve temps.

 

[theonerm2]

There is little difference in the output of a Haswell vs Skylake/Kabylake.

I ran a bench just before disassembly of my i7-4770k @ 4.3Ghz, the i7-7700k even at 5Ghz only pulled ahead by about 20%, certainly mostly the clockspeed difference. So at 4.9Ghz it will be very close indeed. I recall from very early benchmarks that the i7-4790k was even faster in some applications, though that was early BIOS and motherboards/drivers.

The Kabylake series has the usual minor improvements, and some added technology, but brute force computation only improves by as little as 5-10% per generation. Kabylake is effectively Skylake with higher clocks.

I would probably run the 4.8Ghz at 1.28. 1.35 is what my 4770k maxed out at, and the temperatures were crazy. It will probably last a lot longer at 1.28.

I probably will run it at 4.8GHz most of the time. I'll run benchmarks at 4.9GHz though and maybe 5.0GHz if I can reach it.

 

[WildCard999]

What is the voltage & cooler your using with the 4770K? I was able to get a stable 4.4ghz @1.250V with a Corsair H100i, no delid.

Although I will say I've since reverted my OC back to stock since all I really do is game and the OC really made no difference over the stock/boost clocks and having the higher temps during the summer isn't worth it (IMO). The temp difference was about 15C between stock & OC load.

As for the difference between the 4790K & 7700K here's some benchmarks (stock clocks).
http://cpu.userbenchmark.com/Compare/Intel-Core-i7-7700K-vs-Intel-Core-i7-4790K/3647vs2384
With the higher OC it would probably close the performance gap a bit.

I use auto voltage and an H105 cooler to reach 4GHz. I can get a semi stable 4.2GHz at 1.35v. It's really a dud as far as overclocking goes. I got temps in the 70's and low 80's with occt running at 1.35v. My 4770K has been delidded to improve temps.

Try manual voltage, start at 1.25V.

 

[Archer27]

Are you looking for 24/7 reliability? 1.35v is too much for Haswell 24/7 according to the good people here @ Toms(see electromigration https://en.wikipedia.org/wiki/Electromigration).
If I recall correctly they recommend no more than 1.3v due to the FIVR.
1.25 is the starting voltage recommended for 4.6ghz and from there you can figure out your best undervolt or go up for a higher frequency.
The 4790Ks are binned higher and can overclock better in general than the 4770ks due to more and better caps on die as well as a superior TIM under the IHS stock(although delidding provides even lower temps).
If you are able to get 4.8ghz at 1.28 that is an excellent chip and that would be fine to run 24/7.

 

[theonerm2]

Of course I'm going to do my own testing but they said 1.28v at 4.8GHz was possible. By the way. I'm using 2400Mhz RAM.

 

[Archer27]

Of course I'm going to do my own testing but they said 1.28v at 4.8GHz was possible. By the way. I'm using 2400Mhz RAM.

Out of sheer curiosity where did you get this chip? If it was from silconlottery.com I could believe the claim because they are reputable.

On the RAM, you may have to lower the RAM frequency to achieve the CPU frequency you desire.
You will see greater benefit with higher CPU frequency anyways.

 

[theonerm2]

Of course I'm going to do my own testing but they said 1.28v at 4.8GHz was possible. By the way. I'm using 2400Mhz RAM.

Out of sheer curiosity where did you get this chip? If it was from silconlottery.com I could believe the claim because they are reputable.

On the RAM, you may have to lower the RAM frequency to achieve the CPU frequency you desire.
You will see greater benefit with higher CPU frequency anyways.

Siliconlottery.com had a 4790k a few months ago and they said after it sold out that was it for them. They don't sell them anymore. I got this from ebay. So I guess you could say I'm taking a bit of a chance on it.. But we'll see once it comes.

 

[iamacow]

I've been running my i7 4770K @ 1.35v 4.5GHZ for 3 years now. Now i don't do folding or Prime95 all day long but it still stable. 1.4v is too high, 1.35v is nearing the edge if you want to keep the chip for more than 5 years.

 

[theonerm2]

I've been running my i7 4770K @ 1.35v 4.5GHZ for 3 years now. Now i don't do folding or Prime95 all day long but it still stable. 1.4v is too high, 1.35v is nearing the edge if you want to keep the chip for more than 5 years.

I might keep it 2 or 3 years max before I upgrade again. So I'll probably be upgrading to Tiger Lake later on. Crazy we'll still be on the 'lake' cpu's for that long.

 

[Phaaze88]

As long as AMD(or any other company for that matter) keeps Intel on their toes, we may 'rush' through all the other lakes before you know it. XD

 

[synphul]

Many consider 1.35v the upper safe limit for haswell/devil's canyon. Preferred for erring on the side of caution is 1.3v or under. Not to say people haven't run them at higher core voltage but then it may be for one off benchmarking, ultimate overclock tests (competitive) or at the very least, it's their dime.

 

[Archer27]

Many consider 1.35v the upper safe limit for haswell/devil's canyon. Preferred for erring on the side of caution is 1.3v or under. Not to say people haven't run them at higher core voltage but then it may be for one off benchmarking, ultimate overclock tests (competitive) or at the very least, it's their dime.

I did recall reading that Haswells upper limit was 1.35 but it wasn't recommended. Temps get high due to the FIVR(and there is less space on die between transistors(having to make the structure thinner) as well due to having that FIVR, risking further leakage), and the electromigration risk become that much greater, even 5 centivolts more.