AMD back in gear, Centurion FX

[ShintaiDK]

Someone should do a reality check chart on power usage, comparing the power usage by a computer to the power used by air conditioner, washer/dryer, dishwasher, plasma tv, etc.

These peak numbers are cute and all, but irrelevant for most users most of the time. Yeah I get it, if you want to run prime95 all the time then it might be important to you. Or maybe you could make the argument that people who run prime95 all the time obviously don't care about the environment or electricity waste, so what is an extra 100W?

It's a catch-22. Power usage is only remotely relevant if you run your CPU at 100% load 24/7, but if you are running your CPU at 100% load 24/7 you have already proven that you don't care about power usage. I may own 2 FX-8120 CPU, but I can confidently say that with my usage patterns I have used less electricity with these two computers than any single i5 CPU of any generation would use if it was running prime95 24/7 during the same time frame.

Your usage pattern has a huge impact on power, your CPU choice has a relatively minor impact. Reviews should make this more clear, I think a lot of clueless newbies are looking at the peak power usage charts and thinking that they actually use that much power when they are browsing the web. Highly deceptive, IMO.

Our household uses 3Kw/h in average per day. Electricity is ~40cents per Kw/h. I am sure you can figure out the rest

 

[Chiropteran]

Our household uses 3Kw/h in average per day. Electricity is ~40cents per Kw/h. I am sure you can figure out the rest

What I can figure is that if you run prime95 loading your CPU & GPU 24/7 you are going to pay an extra $75+/month for electricity. If you then switched your CPU to an AMD FX and did NOT run prime95, your electricity costs would plummet back down and save you $75/month, give or take a few dollars.

Usage pattern is far more important than your CPU choice.

 

[Durp]

What I can figure is that if you run prime95 loading your CPU & GPU 24/7 you are going to pay an extra $75+/month for electricity. If you then switched your CPU to an AMD FX and did NOT run prime95, your electricity costs would plummet back down and save you $75/month, give or take a few dollars.

Usage pattern is far more important than your CPU choice.

So your solution to AMD's massive power consumption problem is to..... not use the processor. Seems legit.

 

[Rvenger]

What I can figure is that if you run prime95 loading your CPU & GPU 24/7 you are going to pay an extra $75+/month for electricity. If you then switched your CPU to an AMD FX and did NOT run prime95, your electricity costs would plummet back down and save you $75/month, give or take a few dollars.

Usage pattern is far more important than your CPU choice.

I had my FX-8150 OC'd to 4ghz on a killawatt and it only spiked in special situations such as prime 95 or IBT. In gaming it was probably about 30-50 watts more (worst case scenario) average in gaming than my 3770k. Whoopedoo

 

[Charles Kozierok]

Usage pattern is far more important than your CPU choice.

Usage pattern is also a lot more difficult to change than CPU choice.

What you are recommending is the equivalent of telling someone they shouldn't waste time trying to find the most energy-efficient SUV because they could just get a hybrid hatchback. Which is fine -- if the person really only needs a hybrid hatchback.

The other problem is that if you don't care about the cost of power, you probably don't care about saving a few bucks on the CPU either. And if you aren't price-sensitive, what exactly is the selling proposition for AMD chips right now?

 

[Rvenger]

What you are recommending is the equivalent of telling someone they shouldn't waste time trying to find the most energy-efficient SUV because they could just get a hybrid hatchback. Which is fine -- if the person really only needs a hybrid hatchback.

A van is basically useless without hitting the gas pedal... and when you are doing basic tasks on your PC, it still barely uses any power. Not a good comparison IMO.

 

[frozentundra123456]

Someone should do a reality check chart on power usage, comparing the power usage by a computer to the power used by air conditioner, washer/dryer, dishwasher, plasma tv, etc.

These peak numbers are cute and all, but irrelevant for most users most of the time. Yeah I get it, if you want to run prime95 all the time then it might be important to you. Or maybe you could make the argument that people who run prime95 all the time obviously don't care about the environment or electricity waste, so what is an extra 100W?

It's a catch-22. Power usage is only remotely relevant if you run your CPU at 100% load 24/7, but if you are running your CPU at 100% load 24/7 you have already proven that you don't care about power usage. I may own 2 FX-8120 CPU, but I can confidently say that with my usage patterns I have used less electricity with these two computers than any single i5 CPU of any generation would use if it was running prime95 24/7 during the same time frame.

Your usage pattern has a huge impact on power, your CPU choice has a relatively minor impact. Reviews should make this more clear, I think a lot of clueless newbies are looking at the peak power usage charts and thinking that they actually use that much power when they are browsing the web. Highly deceptive, IMO.

I can understand a trade off of using more power to get more performance. For instance going from a dual core to a quad core, or going from a HD7770 to a HD7870. What I dont understand is why one tries to justify using more power for less performance except in certain very specific apps in which the 8350 excels. No matter how "trivial" the power use is to other items in the house, it just seems pointless to use more power for equal or less performance.

And if your usage pattern is idle most of the time, why not just get a dual core?

 

[Chiropteran]

So your solution to AMD's massive power consumption problem is to..... not use the processor. Seems legit.

Nope. I'm saying, for a regular user with regular usage- web browsing, games, unzipping compressed files occasionally- peak power usage is a worthless figure. It applies to maybe 5 minutes of usage a day, the rest of the time your CPU cores are all sitting mostly idle. The difference between an FX-8350 or an i7-3770 works out to pennies a month. Get the CPU you want, because the power usage difference is less than what you spend to iron a shirt.

Peak power usage figures apply if you are running prime95 24/7, sure, but what does that say about you? Intel or AMD CPU, either way you are throwing away $50+ a month in electricity, it is just a question of scale. You could argue that you could save maybe $10 a month by using an Intel CPU, but if you have already demonstrated a willingness to throw away $50 a month what difference does another $10 make? Get the CPU you want, power usage be damned.

And if you aren't price-sensitive, what exactly is the selling proposition for AMD chips right now?

Didn't say there was one. Not really much reason to buy an Intel CPU either though. For most people, the CPU they bought 3-5 years ago is still fine and there is no reason to upgrade. But if you do upgrade, at least look at the factors that matter. Peak power usage for a CPU is largely irrelevant, as a normal person won't run a CPU at peak for more than a few minutes each week.

 

[guskline]

I love these AMD vs Intel vs AMD vs Intel . . . threads. The thread has morphed from FX Centurion to how much power usage of CPUs.

Do we apply the same standard of critical review to GPUs?

BTW, Owning both a 3770k and a FX8350, I find Intel wins on the power/performance basis. The Vishera improved over the Bulldozer but that's not saying much. I just put together another rig with an Asus Sabertooth 990FX Rev 2, FX8320 OC'd to 4.3Ghz, GTX660, 2 ssds, 1 hdd and Thermaltake Water 2.0 Pro and running OCCT for 1 hr showed max wattage used as 317. Idle was 94 watts.

If your usage is what Chiropteron states, I agree with his assessment.

 

[bgt]

Idle was 94 watts.

Thats quite a high idle for a FX. My Fx8350 is 68W idle.

 

[guskline]

Thats quite a high idle for a FX. My Fx8350 is 68W idle.

I notice your FX8350 is stock?

My 8320 is OC'd to 4.3GHZ on all modules/cores and that's the wattage for the entire system less the monitor at idle. I checked it after an hour run of OCCT so I'll run it tonight at idle for awhile after cold boot up to see if it's lower.

 

[Phynaz]

45nm is three generations ago for AMD.??

We were talking of nodes , didnt we?..

Talk about trolling , indeed , you are quite an expert
on this matter , far more than in bear stocks trading,
that s a given.

I was speaking of product. You still didn't answer the question, why would AMD be able to do it when nobody else in the CPU industry can do that anymore? Don't you understand the cost model has changed and they no longer release new processes to manufacturing until they are already almost fully mature?

Kudos on the name calling though. You certainly stay true to form in that when you don't have anything of substance to post.

 

[Unoid]

A van is basically useless without hitting the gas pedal... and when you are doing basic tasks on your PC, it still barely uses any power. Not a good comparison IMO.

Not if the van is down by the river. You can live in it and not need to do anything more than idle the engine (no gas) to charge batteries

 

[thilanliyan]

Get the CPU you want, power usage be damned.

I agree to a certain extent, but cooling becomes a problem when your power consumption is higher. That is my biggest beef with the FX chips, they are harder to cool because of the higher power consumption.

 

[Idontcare]

Not if the van is down by the river. You can live in it and not need to do anything more than idle the engine (no gas) to charge batteries

LOL, I loved Chris Farley (R.I.P.). I still find myself watching Tommy Boy about two months, makes me laugh to this day. "Fat guy in a little coat..."

 

[Ajay]

From the table given before. Vishera @ 5.1 stock fan: 59--61 ºC. I suppose that Centurion would run cooler than an overclocked chip.

The extreme intel series, which is targeting the centurion, are not running much more cooler than that: 70--80 ºC.

That wasn't a stock cooler by any means, go back and re-read it.

 

[Ajay]

LOL, I loved Chris Farley (R.I.P.). I still find myself watching Tommy Boy about two months, makes me laugh to this day. "Fat guy in a little coat..."

Wow, blast from the past! Now you've done it, I'm going to have to watch it this weekend - my wife will hate me [she is NOT a fan]

The scene with Rob Lowe "Did you eat a lot of paint chips when you where a boy?" CF responds "Why" with the perfect expression and intonation, LOL!

 

[Exophase]

Not the same chip. The extreme has more cache and a slightly higher clock.

Same chip with slightly different cache fuse-off. Being allowed to go to a higher clock won't increase idle power consumption. Having more cache will only very slightly impact idle power consumption, at most. A nearly 50W delta between the two can't be justified by differences in the CPUs themselves.

 

[galego]

On the other thread already mentioned I showed that both that figure and the associated energy task figure were completely invalid. I also did an estimation of which would a more realistic value for the FX-8350.

You don't base all your conclusions off one review. Look at a few and take the average.

No. I read and analyse several reviews and then discard those with flawed methodologies or bold ignorance before taking an average.

 

[Abwx]

At stock, FX-8350 4GHz w/turbo disabled, running on an optimized undervoltage (1.268V, measured) cooled by an NH-D14 (max temp 30C) the power consumption at the wall is 276W for Prime95 LargeFFT.

Pushing that up to 4.8GHz, requiring 1.560V for stability (measured), resulted in 55C temperatures and power usage at the wall climbed nearly 200W to 470W.


FX-8350 @ 4.0GHz = 276W (at wall)

FX-8350 @ 4.8GHz = 470W (at wall)

i7-2600K @ 4.8GHz = 251W (at wall)

i7-3770K @ 4.8GHz = 224W (at wall)

Just with theses numbers i would have checked a lot of things
the first being to use the same PSU for all configurations....

Assuming the 470W figure being accurate that makes a CPU
consuming 350W , a power that would destroy it within a
few dozen seconds.

+20% frequency + 24% VDD should at most increase
TDP by 82% while you re saying that it s 150%.....

 

[Exophase]

+20% frequency + 24% VDD should at most increase
TDP by 82% while you re saying that it s 150%.....

That's reasonable for the dynamic power consumption but doesn't take into account increase in the static part (leakage). That's highly temperature dependent and IDC reported a huge increase in temperature from 30C to 55C.

I do think there'd be some other non-linear power consumption effects outside the CPU though. If you look at electrical characteristics for switching regulators like the VRMs on motherboards you will see that not only does quiescent current rise with temperature but the efficiency vs load current tends to have a knee around some point.. if you increase the load current past this knee you'll get less and less efficiency. I doubt these VRMs are optimized for delivering currents well beyond the TDP of the processor so you consume even more power.

No idea how AC/DC (like in the PSU) reacts, a quick look at datasheets seems to show efficiency keeps increasing as load current approaches the maximum the device is rated for, and unlike the VRMs consumer PSUs will be available that really are meant for delivering a big percentage of their rated power..

 

[Ajay]

That's reasonable for the dynamic power consumption but doesn't take into account increase in the static part (leakage). That's highly temperature dependent and IDC reported a huge increase in temperature <did you mean to say static power consumption here?> from 30C to 55C.

I do think there'd be some other non-linear power consumption effects outside the CPU though. If you look at electrical characteristics for switching regulators like the VRMs on motherboards you will see that not only does quiescent current rise with temperature but the efficiency vs load current tends to have a knee around some point.. if you increase the load current past this knee you'll get less and less efficiency. I doubt these VRMs are optimized for delivering currents well beyond the TDP of the processor so you consume even more power.

No idea how AC/DC (like in the PSU) reacts, a quick look at datasheets seems to show efficiency keeps increasing as load current approaches the maximum the device is rated for, and unlike the VRMs consumer PSUs will be available that really are meant for delivering a big percentage of their rated power..

High end overclocking boards ($250+) probably have VRMs designed to handle much higher loads than standard motherboards (< $150).

 

[dastral]

Did everyone miss the undervoltage (1.268V, measured) VS 1.560V for stability (measured).

+200W is ginormous, but going from a "stable undervolt" to "max stable OC" is a huge gap.
I dont doubt your values, but they are visually biased unless someone reads your entire post.
You compare your "best vs worse" scenarios under a specific load.

I'm willing to be bet the same could almost be done with an 3770K : "stable undervolt" vs "MAX OC".
And the results would probably be very similar (albeit not not that enormous) with a 300W CPU....

 

[Phynaz]

I'm willing to be bet the same could almost be done with an 3770K : "stable undervolt" vs "MAX OC".
And the results would probably be very similar (albeit not not that enormous) with a 300W CPU....

How, when there doesn't appear to be a 3770K system that has drawn nearly 500w at the wall?

 

[BrightCandle]

You would struggle to get that sort of draw out of a 3930k in fact, its monstrous amounts of power.