AMD FX-4100e Bulldozer with one module disabled...save energy?

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waltchan

Senior member
Feb 27, 2015
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Lots of people talking here who probably never tinkered with an FX. Lower the voltage and test for stability, there is a lot of possibility there. Especially with a slight down clock. Have a look at my post here while doing a little AVX crunching for power use. In my case a .1 volt decrease saved me over 40 watts on my four module FX. In my experience AM3+ can be quite power friendly, you just have to find your CPU's sweet spot and don't settle for factory defaults.!
Installing Windows 7 with FX-4100e with one module disabled right now, and you're right. Compare to FX-4130 125W at 1.45V I also own vs. FX-4100 65W at 1.26V with one module disabled, it's a dramatic improvement and amount of heat from power supply is now over 2 times less than with FX-4130. What's embarrassing is I only sacrifice 400MHz less in single-thread speed. FX-4130 can only be overclocked up to 4.7GHz max at 1.45V, but put out 2 times more amount of heat from power supply than FX-4100 4.3GHz at 1.26V with one module disabled. So my new set up is more efficient overall. :)

All AMD FM2 Trinity dual-core APUs are one module (based on Bulldozer), and rates only 65W. For quad-core two modules, TDP increases to 100W.
 
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waltchan

Senior member
Feb 27, 2015
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Undervolting / underclocking it makes a lot more sense if you want to reduce power use, imo.
The Gigabyte board automatically downgrades the voltage with turbo off, depending on CPU quality and way it's built. Some FX-4100s stay stuck at 1.40V with turbo off (I'll sell them soon), but this one I have is rated only 1.26V with turbo off. Turn on turbo increases to 1.40V, and CPU fan runs insanely fast.
 
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zir_blazer

Golden Member
Jun 6, 2013
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Not really. Selection is very limited here. AM3 is insanely slow with Athlon 170u, average-power in Athlon X4 610e, and good-speed in FX-4100. I previously had a Athlon X4 610e overclocked at 3.0GHz, and still found it too slow. Then I put in FX-4100 overclocked at 4.3GHz, and it overheated badly with the cheap heatsink size from FM2 Richland, so I was forced to disable one module. Works okay now.
A 2-core FX-4100 should be SLOWER overall than your older overclocked AIIX4 610e @ 3 GHz. It may win in Single Threading tasks, lose in everything else.

It is not even a Piledriver FX-4300, is a 4 years old Bulldozer! Pointless downgrade.
 
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Yuriman

Diamond Member
Jun 25, 2004
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The Gigabyte board automatically downgrades the voltage with turbo off, depending on CPU quality. Some FX-4100s stay stuck at 1.40V with turbo off (I'll sell them soon), but this one I have is rated only 1.26V with turbo off.

It's not the board (or at least, I don't believe it's the board), but rather, the CPU's voltage table. At least with Intel CPUs, if you leave the voltage on "auto", it will change depending on the clocks you select.

You might be interested in my thread here, where I explored the peak efficiency point of my 22nm Ivy Bridge CPU.

Yuriman said:
Some food for thought: If we assume ~5w idle draw, under an AVX load and accounting for PSU efficiency @ ~80%, an Ivy Bridge desktop chip draws ~12w at 1600MHz, ~21w at 2600MHz, and ~36w at its maximum non-turbo frequency of 3400MHz. Going up another 600MHz increases power consumption by almost 50%, which makes it pretty clear why the stock frequency is what it is.

A factor to consider in the equation is how much the rest of your system draws; At idle, it's probably far more than the CPU alone, and at- or near-idle is where your system will probably spend most of its time. Although my 3570K actually gets continuously more efficient at lower clocks, if you factor in total system power draw, it actually peaks around 3.1ghz. If I were to drop my total system power consumption, the point of peak efficiency would be lower.

I expect since AM3 is built on an older process and has both a north and south bridge, the motherboards with that socket probably use a lot more power, though it's worth exploring - this is only supposition on my part.

EDIT: Is it possible, OP, to sell some of these older AMD systems and replace them with a single faster, quieter and lower power consuming system? Even going socket FM2+ would be a large improvement.
 
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waltchan

Senior member
Feb 27, 2015
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I think the point is that if you cripple the chip, the remaining module is probably going to have to work it's little ass off to get the jobs done, cancelling out any power benefits.
It's true, I agree. But the small heatsink I put in came from 65W FM2 Richland box. It doesn't do well with two modules on. Fan runs insanely fast. I was forced to disable one-module and learn to live with it, and fan now runs a little quieter. So it indicates it's using less power now.
 

waltchan

Senior member
Feb 27, 2015
846
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A 2-core FX-4100 should be SLOWER overall than your older overclocked AIIX4 610e @ 3 GHz. It may win in Single Threading tasks, lose in everything else.

It is not even a Piledriver FX-4300, is a 4 years old Bulldozer! Pointless downgrade.
Single-thread in Athlon 640 (610e equivalent at 3.0GHz) is only 1032. I couldn't stand it. But I do miss the four cores.
 

waltchan

Senior member
Feb 27, 2015
846
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EDIT: Is it possible, OP, to sell some of these older AMD systems and replace them with a single faster, quieter and lower power consuming system? Even going socket FM2+ would be a large improvement.
I bought the Gigabyte GA-78LMT-USB3 board for only $19.99 on Black Friday. Sold out in less than one hour. It was at Newegg. FM2 boards are higher and APUs aren't cheap. Who wants a A4-4000 for $33 shipped. AM1s are also a joke.
 
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Yuriman

Diamond Member
Jun 25, 2004
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I bought the Gigabyte GA-78LMT-USB3 board for only $19.99 on Black Friday. Sold out in less than one hour. It was at Newegg. FM2 boards are higher and APUs aren't cheap. Who wants a A4-4000 for $33 shipped. AM1s are also a joke.

True, but with AM3, you have to buy a video card too, and a discrete card consumes a lot more power than an iGPU. What do you use your systems for? The included iGPU on FM2 is likely far superior to a discrete card that you could get for the cost difference between the two platforms, and you'd have a faster and less thirsty CPU to boot.
 

waltchan

Senior member
Feb 27, 2015
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True, but with AM3, you have to buy a video card too, and a discrete card consumes a lot more power than an iGPU. What do you use your systems for? The included iGPU on FM2 is likely far superior to a discrete card that you could get for the cost difference between the two platforms, and you'd have a faster and less thirsty CPU to boot.
Not this one. This board has integrated Radeon HD3000 GPU. Has HDMI output. It's better than nothing.
 
Feb 25, 2011
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For the same money, wouldn't a G1820 be more efficient? You can get an ASRock ITX B85 motherboard right now at Newegg for $44.99 + $0.99 ship.

Depends on what your power target is.

Based on the Skylake review, it looks like a Skylake CPU may idle 2-3w less than a Haswell.

That's not small potatoes if you're trying to build a NUC-like that idles at 10w or less.

The newer kit is more expensive though.
 

Yuriman

Diamond Member
Jun 25, 2004
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My guess is that the HD3000 draws significantly more power than the iGPU on Intel and AMD's modern CPUs. When I replaced the HD4870 in my main rig with my HD7850, for instance, my system's total idle power consumption dropped by a whopping 50% - from a video card replacement alone.
 

waltchan

Senior member
Feb 27, 2015
846
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My guess is that the HD3000 draws significantly more power than the iGPU on Intel and AMD's modern CPUs. When I replaced the HD4870 in my main rig with my HD7850, for instance, my system's total idle power consumption dropped by a whopping 50% - from a video card replacement alone.
That's right. HD3000 integrated GPU is a joke installed for AM3 boards. Takes at least 50% of total power to run, hence I can only use "e" or "u" processors. AMD could care less for our environment.
 

MiddleOfTheRoad

Golden Member
Aug 6, 2014
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That's right. HD3000 integrated GPU is a joke installed for AM3 boards. Takes at least 50% of total power to run, hence I can only use "e" or "u" processors. AMD could care less for our environment.

The HD3000 is an antique. $19.99 was probably too much honestly (I bought a AM3+ motherboard for $9.99 after rebate about 2 years ago)... You can usually get 1150 motherboards for $29 from Newegg.

The HD3000 is practically unusable today. It's a 55nm chip with only 4 TMU's and 4 ROP's -- the chip runs @ 344 Mhz.
 

Techhog

Platinum Member
Sep 11, 2013
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He already mentioned that he has a am3+ mb which is why he wants to stick with fx.

If he's this concerned about power consumption, it's better to save up $100 for a Pentium + MB and then dump the old board. There's just no point in trying to save power on this platform.
 

MrTeal

Diamond Member
Dec 7, 2003
3,919
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That's right. HD3000 integrated GPU is a joke installed for AM3 boards. Takes at least 50% of total power to run, hence I can only use "e" or "u" processors. AMD could care less for our environment.

What are you talking about? The IGP is on the chipset and won't affect the power delivery of the MB to the CPU. And while it's 55nm and not terribly efficient by modern standards, it's also so underwhelmingly weak that it will still only draw 5 or 6W. Blaming AMD because you bought a 6 year old chipset is ridiculous.
 

DrMrLordX

Lifer
Apr 27, 2000
23,133
13,230
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Just undervolt the CPU already. You can probably get it down without even having to underclock.
 

VirtualLarry

No Lifer
Aug 25, 2001
56,587
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That's right. HD3000 integrated GPU is a joke installed for AM3 boards. Takes at least 50% of total power to run, hence I can only use "e" or "u" processors. AMD could care less for our environment.

?

:(

Or the person BUYING THE PC could care less about the environment... there are more power-efficient chips available. (Most of them say "Intel" though.)
 

waltchan

Senior member
Feb 27, 2015
846
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81
Just undervolt the CPU already. You can probably get it down without even having to underclock.
The Gigabyte board automatically undervolts the CPU with turbo off from 1.40V to 1.26V, depending on each CPU quality, but it won't let me let me adjust the volts manually. Overall, I found its power consumption very close to Athlon X4 610e earlier. While the Athlon 610e only runs at 1.13V, the 760g chipset runs hotter than with FX-4100e due to bus CPU & memory overclocking. I gain 1.6 times more in single-thread speed in FX-4100e with one module disabled, but I lose the multitasking speed from Athlon 610e.
 
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VirtualLarry

No Lifer
Aug 25, 2001
56,587
10,225
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The Gigabyte board automatically undervolts the CPU with turbo off from 1.40V to 1.26V, depending on each CPU quality, but it won't let me let me adjust the volts manually. Overall, I found its power consumption very close to Athlon X4 610e earlier. While the Athlon 610e only runs at 1.13V, the 760g chipset runs hotter than with FX-4100e due to bus CPU & memory overclocking. I gain 1.6 times more in single-thread speed in FX-4100e with one module disabled, but I lose the multitasking speed from Athlon 610e.

If you are only going to be running 2 threads / 1 module, on a Bulldozer FX chip, and overclocking for single-threaded speed... *shakes head*. Why not a G3258 combo? So much more power-efficient, so much better single-threaded speed.

Edit: Not to mention, a "modern" platform. (First time I think I've ever referring to an H81 mobo as "modern".)
 

waltchan

Senior member
Feb 27, 2015
846
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If you are only going to be running 2 threads / 1 module, on a Bulldozer FX chip, and overclocking for single-threaded speed... *shakes head*. Why not a G3258 combo? So much more power-efficient, so much better single-threaded speed.

Edit: Not to mention, a "modern" platform. (First time I think I've ever referring to an H81 mobo as "modern".)
I already have a LGA1150 on my desk, which is a Celeron G1850 running Windows 10. My desk requires 5 different PCs with 5 different sockets, 5 different operating systems (from XP to 10), and 5 different motherboard brands. I keep everything diverse here and never discriminate any brand. I found AM3+ works best with Windows 7 only.
 

VirtualLarry

No Lifer
Aug 25, 2001
56,587
10,225
126
I already have a LGA1150 on my desk, which is a Celeron G1850 running Windows 10. My desk requires 5 different PCs with 5 different sockets, 5 different operating systems (from XP to 10), and 5 different motherboard brands. I keep everything diverse here and never discriminate any brand. I found AM3+ works best with Windows 7 only.

Well, I guess I didn't understand your requirements for "computing diversity". I won't ask why, and don't pretend to understand why either, but I'm sorry for giving you a hard time about your choice, if you already have an 1150 as your primary rig. Carry on, and have fun!
 

DrMrLordX

Lifer
Apr 27, 2000
23,133
13,230
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The Gigabyte board automatically undervolts the CPU with turbo off from 1.40V to 1.26V, depending on each CPU quality, but it won't let me let me adjust the volts manually.

Drat! Stupid budget BIOSes. Okay. Can you tweak your voltages downward with something like amdmsrtweaker?