The most power efficient gaming CPU you can get in early 2020

[Islam Ghunym]

What are the actual technical differences between I9 CPUs?!?!

 

I mean, I got it, one 35W TDP, other 65 and last 95W.

the 9900T base at 2.0 GHz then boost up to 4.4GHz (using 60-60W) depending on demands. not all cores can boost to 4.4 as these clocks goes down when more cores are needed by appliccations, but the 9900K can boost to 5.0 GHz (using freakin 165W to 180W!!).

 

using Intel XTU I can't set the turbo multiplier, right? not even on any bios, right?

the actuall question is: can you make a 9900T level of efficiency out of a 9900K while getting the same max clock speed (4.4 of 9900T at 1 core)?

will limiting the TDP of  a 9900K to 35W makes the 9900K behave like a 9900T if base clock has been lowered or some voltage offsets applied or changing other stuff like long and short duration, maximum current and so on?

can you make the 9900T clocks behave like a 9900 with power tweaks?

 

I need some detailed info about required tweaks if that is possible.

Edited March 5, 2020 by Islam Ghunym
The actual question

[Fasauceome]

The only differences between these CPUs are the clocks and voltages. You can turn a 9900K down to behave just like a 9900T.

22 minutes ago, Islam Ghunym said:

can you make the 9900T clocks behave like a 9900 with power tweaks?

no, Intel locks down the clocks on their non-K models to avoid the problems they had with the 2600K vs 2700K way back in the day. Any low end SKU that can match a higher end one will cannibalize the lineup.

[Bombastinator]

So you want to downclock/undervolt a 9900k to 9900T specs?  Not sure it’s possible.  Might be.  Intel had a habit in the past of using the same CPU off the line and just turning bits of it off to make cheaper chips. I don’t know how much of that they still do.  The 9900t has a very different power profile than the 9900k.  The problem is the actual on die differences are something of an intel secret.  It’s possible it’s firmware.  Might also be laser cut connections on the die though.  They might also be different dies.

 

if you want to turn a 9900t into a 9900k It becomes extremely unlikely.  Like very near zero.  Intel would have gone to lengths to make it impossible, even if the chips came off the same assembly line.  Intel would have had to make a serious mistake for it to even be possible.

[Islam Ghunym]

22 minutes ago, Fasauceome said:

The only differences between these CPUs are the clocks and voltages. You can turn a 9900K down to behave just like a 9900T.

cool, I can undervolt the 9900K and match it's base clock to 9900T one, but will the CPU perform exactly like a 9900T with max boost clock 4.4? or I have to tweak other things.

 

22 minutes ago, Fasauceome said:

no, Intel locks down the clocks on their non-K models to avoid the problems they had with the 2600K vs 2700K way back in the day. Any low end SKU that can match a higher end one will cannibalize the lineup.

what I meant is: 9900T has maybe power limits that stop it from having higher clocks or boosting for longer durations so if I turned those off, will the 9900T takes as much power as possible to sustain higher boosting clocks so it reaches the 9900 non-k level of performance?

the 8700T has been already tested and it seems to perform like 8700 when limits are disabled, but that is a different CPU.

[Stormseeker9]

38 minutes ago, Islam Ghunym said:

What are the actual technical differences between those CPUs?!?!

 

I mean, I got it, one 35W TDP, other 65 and last 95W.

the 9900T base at 2.0 GHz then boost up to 4.4GHz (using 60-60W) depending on demands. not all cores can boost to 4.4 as these clocks goes down when more cores are needed by appliccations, but the 9900K can boost to 5.0 GHz (using freakin 165W to 180W!!).

 

using Intel XTU I can't set the turbo multiplier, right? not even on any bios, right?

the actuall question is: can you make a 9900T level of efficiency out of a 9900K while getting the same max clock speed (4.4 of 9900T at 1 core)?

will limiting the TDP of  a 9900K to 35W makes the 9900K behave like a 9900T if base clock has been lowered or some voltage offsets applied or changing other stuff like long and short duration, maximum current and so on?

can you make the 9900T clocks behave like a 9900 with power tweaks?

 

I need some detailed info about required tweaks if that is possible.

9900 = not overclockedable 

9900K = unlocked multiplier, so overclockable

9900T= low power draw design (so could be used in laptop/tablet if needed to be)

 

 

 

Please correct me if I’m wrong but this is from my own knowledge 

[Fasauceome]

4 minutes ago, Islam Ghunym said:

cool, I can undervolt the 9900K and match it's base clock to 9900T one, but will the CPU perform exactly like a 9900T with max boost clock 4.4? or I have to tweak other things.

 

the only performance difference is the clock speed. They have the same cache, same microarchitecture, etc.

[Islam Ghunym]

4 minutes ago, Fasauceome said:

the only performance difference is the clock speed. They have the same cache, same microarchitecture, etc.

as far as i know: any changes to multipliers in bios will negate CPU boosting and that will result in very poor performance if it stays at 2.0 Ghz all the time especially in games,is that true?

[Fasauceome]

1 minute ago, Islam Ghunym said:

as far as i know: any changes to multipliers in bios will negate CPU boosting and that will result in very poor performance if it stays at 2.0 Ghz all the time, is that true?

If the CPU is stuck at 2.0 GHz, yes that will hinder performance. Most motherboards (from MSI and Asus at least) offer a per core boost so you can set the multiplier for specific workloads.

[Islam Ghunym]

12 minutes ago, Fasauceome said:

If the CPU is stuck at 2.0 GHz, yes that will hinder performance. Most motherboards (from MSI and Asus at least) offer a per core boost so you can set the multiplier for specific workloads.

so people buy the 9900T becasue it does that boosting mechanism automatically to favour power and looks like making a 9900K works as a 9900T will require changing multipliers individually depending on the workload. does not seem to be achievable, but relatively close. I would go for ryzen 7 3700X 7nm, but that CPU does not make use of power well.  it takes 95W to reach 4.15GHz and takes even more to reach the 4.4 GHz while it is advertised at 65W. the biggest issue is that if I disabled PBO and precesion boost. it will stay at 3.6Ghz and it gives a decent efficiency (40W maybe) more than intel 14nm T variants which goes between 50 and 60w, but intel has it's own great boosting mechanism that reaches 4.4GHz for one core on the I9 at bellow 60w and ryzne 7 will stuck at 3.6

 

could that issue be fixed someway with ryzen?

[Fasauceome]

2 minutes ago, Islam Ghunym said:

so people buy the 9900T becasue it does that boosting mechanism automatically to favour power and looks like making a 9900K works as a 9900T will require changing multipliers individually depending on the workload

it's also significantly cheaper, which is kinda the main draw.

 

2 minutes ago, Islam Ghunym said:

I would go for ryzen 7 3700X 7nm, but that CPU does not make use of power well.  it takes 95W to reach 4.15GHz and takes even more to reach the 4.4 GHz while it is advertised at 65W

TDB figures are bogus. The 9900K consumes quite a lot more power than the 3700X but their performance is almost the same.

 

3 minutes ago, Islam Ghunym said:

could that issue be fixed someway?

don't use TDP as a power measurement, it's a thermal measurement anyway. It stands for "thermal design power"

[Islam Ghunym]

7 minutes ago, Fasauceome said:

TDB figures are bogus. The 9900K consumes quite a lot more power than the 3700X but their performance is almost the same.

I mainly play games, but I am very limited in power matter as I am working and playing on batteries, but I won't go for laptops as I don't like fixed non-tweakable stuff and are far more expensive.

I really need a very power efficient CPU that will deliver stable frame timings in any game from 2000 to 2020 so I need the power of intel's single core as multicore performance does not matter for me, but numbers of cores and threads does.

[Fasauceome]

3 minutes ago, Islam Ghunym said:

multicore performance does not matter for me, but numbers of cores and threads does.

this doesn't make any sense

 

if the number of cores and threads matters, then multicore performance matters. If single core was the only factor, don't look at 8 cores. If you're interested in gaming only, the Ryzen 3600 would be a really good call.

 

AMD CPUs are really power efficient, you should consider Ryzen instead of Coffee lake.

[Islam Ghunym]

27 minutes ago, Fasauceome said:

if the number of cores and threads matters, then multicore performance matters. If single core was the only factor, don't look at 8 cores. If you're interested in gaming only, the Ryzen 3600 would be a really good call.

I know, but my english is not good enough to explain what I actually meant.

the thing is that each game uses the CPU in a different way. Intel CPU adapts to all these needs so if the applications needs less cores but higher clocks, the CPU will decide how to behave unlike AMD which do boost on all cores whenever it can and usually it fails to boost some cores. some old tiles I play make use of 1 core very much ex: from 60% to 100% causing stutters in some cases on AMD but not on intel because intel boosts well (short duration can be enough to deliver the intended demands). what I wanted to say is bellow 4.2 is not enough for me.

however most new games uses all cores properly so that high clock speeds of all cores from AMD compared to intel does not matter so that multi core performance does not matter as a value that is higher on AMD CPUs, but the number of cores/threads does.

[Zando_]

29 minutes ago, Fasauceome said:

AMD CPUs are really power efficient, you should consider Ryzen instead of Coffee lake.

^^ If you're worried about power, grab a 3600 or 3600X and drop clocks as low as you can while still running your games well, then undervolt. 

 

Main advantage of Intel chips is lower latencies and higher clock headrooms, but at a much higher power consumption. Since you're power limited, an Intel chip won't clock high, meaning you won't be able to beat the Ryzen anyways. For this use case you'll be looking for performance per watt, and manually tuned Zen 2 is going to crush any Intel chip on that front. 

[Fasauceome]

28 minutes ago, Islam Ghunym said:

Intel CPU adapts to all these needs so if the applications needs less cores but higher clocks, the CPU will decide how to behave unlike AMD which do boost on all cores whenever it can and usually it fails to boost some cores. some old tiles I play make use of 1 core very much ex: from 60% to 100% causing stutters in some cases on AMD but not on intel because intel boosts well (short duration can be enough to deliver the intended demands). what I wanted to say is bellow 4.2 is not enough for me.

This doesn't make any sense. I believe you are misunderstanding how CPUs work.

[Islam Ghunym]

2 hours ago, Zando Bob said:

^^ If you're worried about power, grab a 3600 or 3600X and drop clocks as low as you can while still running your games well, then undervolt. 

 

Main advantage of Intel chips is lower latencies and higher clock headrooms, but at a much higher power consumption. Since you're power limited, an Intel chip won't clock high, meaning you won't be able to beat the Ryzen anyways. For this use case you'll be looking for performance per watt, and manually tuned Zen 2 is going to crush any Intel chip on that front. 

Droping clocks by itself is a problem, this sucks. Idk what I should take.

I need a CPU that can boost well like intel.

Intel 9900T probably does that peaking high wattage each  time required, but since it does that for short duration ot won't suck much power. AMD chips could be better, but I need the benfit of boosting mechanism

[Islam Ghunym]

2 hours ago, Fasauceome said:

This doesn't make any sense. I believe you are misunderstanding how CPUs work.

Nope, I am totally right. If you can prove that I was very wrong, go head.

I may learn something from you.

[Zando_]

1 minute ago, Islam Ghunym said:

Droping clocks by itself is a problem, this sucks. Idk what I should take.

I need a CPU that can boost well like intel.

Intel 9900T probably does that peaking high wattage each  time required, but since it does that for short duration ot won't suck much power. AMD chips could be better, but I need the benfit of boosting mechanism

 

1 minute ago, Islam Ghunym said:

Nope, I am totally right. If you can prove go head.

Not in the slightest. Intel Turbo Boost is pretty simple, it has a set multiplier it uses based off core load only. It never changes unless you hit throttling temps (around 100C), then it downclocks the CPU to protect itself. It's not "smart" at all, it's just a basic boost. 

AMD's PBO (precision boost overdrive) that now comes with every Zen 2 chip out there is much "smarter". It takes into account what voltage and thermal headroom it has, then sees what cores and how many cores are under load, and how heavily they are loaded, then boosts accordingly. It's a far, far better boost than Intel's. 

You've got them reversed, Intel has a basic boost function and mostly gains from manual overclocking, AMD's CPUs have a much, much better boost that usually results in the best performance for everything but a purely all core load with 80-100% on all said cores. 

You'll be using neither if you want the lowest power consumption possible, so it doesn't even matter. For the use case you've claimed, you need to downclock the CPUs to the lowest clock where they still run your games acceptably, then undervolt as low as you can while keeping it stable. You can use offsets to have voltage automatically drop further when the CPU isn't under load as well, so idle consumption will be barely affected. Ryzen chips on the Zen 2 arch will be much better here, they have a higher IPC (similar performance at lower clocks than an Intel chip) and a very low power consumption for their performance already, and you could manually tune them to pull even less. An Intel chip forced into a power consumption that small would likely clock - and therefore perform - much worse. Especially since Intel's current gen IPC is lower than AMD's, meaning they need noticeably higher clocks to compete performance wise. That and they're based on ringbus, which scales terribly at much above 4 cores (and the 9900 series CPUs are 8c/16t) on both heat and power consumption. 

[Islam Ghunym]

7 minutes ago, Zando Bob said:

 

Not in the slightest. Intel Turbo Boost is pretty simple, it has a set multiplier it uses based off core load only. It never changes unless you hit throttling temps (around 100C), then it downclocks the CPU to protect itself. It's not "smart" at all, it's just a basic boost. 

AMD's PBO (precision boost overdrive) that now comes with every Zen 2 chip out there is much "smarter". It takes into account what voltage and thermal headroom it has, then sees what cores and how many cores are under load, and how heavily they are loaded, then boosts accordingly. It's a far, far better boost than Intel's. 

You've got them reversed, Intel has a basic boost function and mostly gains from manual overclocking, AMD's CPUs have a much, much better boost that usually results in the best performance for everything but a purely all core load with 80-100% on all said cores. 

You'll be using neither if you want the lowest power consumption possible, so it doesn't even matter. For the use case you've claimed, you need to downclock the CPUs to the lowest clock where they still run your games acceptably, then undervolt as low as you can while keeping it stable. You can use offsets to have voltage automatically drop further when the CPU isn't under load as well, so idle consumption will be barely affected. Ryzen chips on the Zen 2 arch will be much better here, they have a higher IPC (similar performance at lower clocks than an Intel chip) and a very low power consumption for their performance already, and you could manually tune them to pull even less. An Intel chip forced into a power consumption that small would likely clock - and therefore perform - much worse. Especially since Intel's current gen IPC is lower than AMD's, meaning they need noticeably higher clocks to compete performance wise. That and they're based on ringbus, which scales terribly at much above 4 cores (and the 9900 series CPUs are 8c/16t) on both heat and power consumption. 

 What about silicon bining.

Will I get better better efficiency with 8 cores 3700X or it should do as 3600X do when downclocked in term of power consumption.

It will be ok if the 8 core ryzen 7 takes the same power of ryzen 5 3600. What do you expect?

[Zando_]

2 minutes ago, Islam Ghunym said:

 What about silicon bining.

Will I get better better efficiency with 8 cores 3700X or it should do as 3600X do when downclocked in term of power consumption.

It will be ok if the 8 core ryzen 7 takes the same power of ryzen 5 3600. What do you expect?

3800X is the better binned version of a 3700X, the 3600X is the better binned version of the 3600. I don't know how the 8c power consumption compares to the 6c, but I do know they can fit more cores in the same package with the same power due to chiplet binning (see the 3950X consuming about the same as the 3900X but having more cores). 

[Islam Ghunym]

5 minutes ago, Zando Bob said:

3800X is the better binned version of a 3700X, the 3600X is the better binned version of the 3600. I don't know how the 8c power consumption compares to the 6c, but I do know they can fit more cores in the same package with the same power due to chiplet binning (see the 3950X consuming about the same as the 3900X but having more cores). 

Yup 2 chiplets, each one can have 4 cores. So then I should go for 3800X then disable everyboost and undervolt as required then try to certain clocks untill I reach good power consumption and good clocks... I can see later what is suitable, right?

[Zando_]

2 minutes ago, Islam Ghunym said:

Yup 2 chiplets, each one can have 4 cores. So then I should go for 3800X then disable everyboost and undervolt as required then try to certain clocks untill I reach good power consumption and good clocks... I can see later what is suitable, right?

3800X is probably the better chip, and if you absolutely have to lower power consumption even more, you can likely disable cores as well. 

[Islam Ghunym]

Just now, Zando Bob said:

3800X is probably the better chip, and if you absolutely have to lower power consumption even more, you can likely disable cores as well. 

Cool, maybe I can set 2 profiles, one with 4 cores higher clocks and other with all 8 cores. I will see if 6 cores are better. Thanks very much

[Islam Ghunym]

6 minutes ago, Zando Bob said:

3800X is probably the better chip, and if you absolutely have to lower power consumption even more, you can likely disable cores as well. 

Just 1 more thing. Will motherbiard vrm play a rule on how good my cpu clocks can go at certain power consumption?

[Zando_]

Just now, Islam Ghunym said:

Just 1 more thing. Will motherbiard vrm play a rule on how good my cpu clocks can go at certain power consumption?

Not really, so long as you're not getting a really shitty board. Anything with decent VRMs should handle the 8 core chips fine.