Take a look at our
ThinkPads.com HOME PAGE
For those who might want to contribute to the blog, start here: Editors Alley Topic
Then contact Bill with a Private Message
ThinkPads.com HOME PAGE
For those who might want to contribute to the blog, start here: Editors Alley Topic
Then contact Bill with a Private Message
RAM frequency vs. power consumption for Carolina idiots
RAM frequency vs. power consumption for Carolina idiots
As I continue my journey down the path of hardware hacker, I'd like some help from someone who knows more about RAM than I do (which.... is probably most people!)
Given a system with two channels of DDR3, is there an appreciable difference in power draw when populating them with modules that run at 1600, 1866, and 2133? If so, any ballpark figures? (Assume the same size for each, let's say... 8GB per module?)
Thanks in advance. I feel a bit silly bothering you guys over something so trivial, but I'll be darn if I can actually find a straight answer to this anywhere on the web. (Most of the RAM freq. discussions are more desktop-oriented, and the laptop ones quickly devolve into people arguing over whether the higher freqs are necessary.)
Given a system with two channels of DDR3, is there an appreciable difference in power draw when populating them with modules that run at 1600, 1866, and 2133? If so, any ballpark figures? (Assume the same size for each, let's say... 8GB per module?)
Thanks in advance. I feel a bit silly bothering you guys over something so trivial, but I'll be darn if I can actually find a straight answer to this anywhere on the web. (Most of the RAM freq. discussions are more desktop-oriented, and the laptop ones quickly devolve into people arguing over whether the higher freqs are necessary.)
Need help with Linux or FreeBSD? PM or catch me on IRC: I'm ThinkRob on FreeNode and EFnet.
Laptop: X270, running Fedora
Desktop: Intellistation 285 (currently dead)
Workstation: owned by my employer
Toy: Miata!
Laptop: X270, running Fedora
Desktop: Intellistation 285 (currently dead)
Workstation: owned by my employer
Toy: Miata!
-
- ThinkPadder
- Posts: 1461
- Joined: Fri Oct 11, 2013 7:45 pm
- Location: North Ridgeville, Ohio, United States
- Contact:
Re: RAM frequency vs. power consumption for Carolina idiots
Ray is probably the best one to answer this one, maybe he'll chime in.
My thought is that for a given voltage you'll see more power draw and heat on the higher clock speeds, in much the same way you see that with CPU frequencies. It's probably negligible with RAM, but it's true... I've never seen it discussed or written about before!
My thought is that for a given voltage you'll see more power draw and heat on the higher clock speeds, in much the same way you see that with CPU frequencies. It's probably negligible with RAM, but it's true... I've never seen it discussed or written about before!
T480 with T25 keyboard | T25 | W520 i7-2860QM·Quadro 2000m·IPS FHD | T601F T9900·NVS 140m·LED AFFS UXGA
T420 IPS FHD | X220 IPS FHD | T61p·T61·43·42p|X13 Yoga G3·220T·301·41T·24·23·22|G41|A31p·22m|i1200|TransNote
600|770Z|770|760XD|760EL|701C|755C
T420 IPS FHD | X220 IPS FHD | T61p·T61·43·42p|X13 Yoga G3·220T·301·41T·24·23·22|G41|A31p·22m|i1200|TransNote
600|770Z|770|760XD|760EL|701C|755C
-
- Senior Member
- Posts: 817
- Joined: Fri Oct 17, 2014 8:13 pm
- Location: kingston, ontario, Canada
Re: RAM frequency vs. power consumption for Carolina idiots
Even better. When you have run the DDR3 2133 or 1866 at 1600, will produce less heat and even more better when notebook (ivy bridge, Haswell and later processors) using DDR3L which is less heat even more running at 1600 using 1866/2133 DDR3L at 1.35V vs 1.5V. Combine that both, you have double bingo on less power use. Dual channel is best especially with integrated GPU.
What is your notebook?
Cheers, thinkpadcollection
What is your notebook?
Cheers, thinkpadcollection
Re: RAM frequency vs. power consumption for Carolina idiots
But that's not strictly true with CPUs though, is it? The TDP is often the same across different frequencies of the same model CPU (ex: the i5-3320M and i5-3340M have the same TDP despite the latter having a base freq. of 2.7 GHz vs 2.6 GHz). It's just a bit more confusing with CPUs since they're not usually running flat-out (so the "hurry up and sleep" approach means that a faster chip can get into a deeper C-state faster, and thus use less power over a given period.)My thought is that for a given voltage you'll see more power draw and heat on the higher clock speeds, in much the same way you see that with CPU frequencies. It's probably negligible with RAM, but it's true... I've never seen it discussed or written about before!
I know that for RAM the difference *should* be minimal, but as you pointed out, there's not really any discussion of it anywhere.
Need help with Linux or FreeBSD? PM or catch me on IRC: I'm ThinkRob on FreeNode and EFnet.
Laptop: X270, running Fedora
Desktop: Intellistation 285 (currently dead)
Workstation: owned by my employer
Toy: Miata!
Laptop: X270, running Fedora
Desktop: Intellistation 285 (currently dead)
Workstation: owned by my employer
Toy: Miata!
-
- Senior Member
- Posts: 837
- Joined: Wed May 19, 2010 11:21 pm
- Location: Pardubice, Czech Republic
- Contact:
Re: RAM frequency vs. power consumption for Carolina idiots
TDP isn't power draw, it's an indicator of heat dissipation.
T420 i7 3612QM seabios; T420 i7 3630QM; T400 Q9100 seabios; T61 P9600; T60 libreboot; x62; x60s libreboot, led; x24 xiphmont led
-
- Senior Member
- Posts: 817
- Joined: Fri Oct 17, 2014 8:13 pm
- Location: kingston, ontario, Canada
Re: RAM frequency vs. power consumption for Carolina idiots
Quality of same silicon varies across same slice of dies. They are tested and programmed to best use most of same slice. For example fewer crop of cream processors for xeon and ones that does not make the cut for xeon gets i7 and plenty of i5 that does not make it to i7 status. So on. Now, new dimension to this is all the processors also had to be tested again for target TDP at different frequency for all of them. The best die tend to be running cooler at higher frequency anything else get sorted on different frequencies while meeting target of wattage but not exceed TDP. Overclocking is possible because of margin is calculated during design phase of new silicon spin during design work of specific percentage. I had little luck with overclock back then so I didn't bother.
Cheers, thinkpadcollection
Cheers, thinkpadcollection
-
- Admin
- Posts: 10327
- Joined: Sun Jun 04, 2006 1:26 am
- Location: San Jose, CA 95120 USA
- Contact:
Re: RAM frequency vs. power consumption for Carolina idiots
Here's my take on this, from years (decades, even) of a memory test engineering background. Given that the memory clock speed is kept constant in Thinkpads (I'm assuming that all current and past designs do NOT adjust their clock speed when presented with memory modules that have a higher speed rating than what was initially available when the laptop motherboard was designed AND that no hardware tweaks have been done, read: BIOS does not adjust memory clock given the module's SPD information and there's no overclocking), then the "newer and faster" modules will probably draw less current. However, to be sure, you'll need to carefully consult the published datasheets of the modules that you intend using. Note that the current consumption limits in datasheets are MAXIMUM values, although in some cases you'll be given "typical" values. This means that the memory module manufacturer guarantees that the module will not draw more than the specified maximum value, but it will often operate at a somewhat lower value. Power consumption of memory modules does depend primarily upon the clock frequency it runs at. Given a PC3-17000 (2133Mhz) rated module, it will consume less current than it's typical value if put in a system that's speed locked at PC3-12800 (1600Mhz). How much less can sometimes be determined from the datasheet.
Is there an appreciable difference? Probably not. We're talking a couple of mA here and there. That might equate to a few minutes of runtime when operating on a battery and probably no discernible difference in the amount of heat that pours out the side.
Is there an appreciable difference? Probably not. We're talking a couple of mA here and there. That might equate to a few minutes of runtime when operating on a battery and probably no discernible difference in the amount of heat that pours out the side.
Ray Kawakami
X22 X24 X31 X41 X41T X60 X60s X61 X61s X200 X200s X300 X301 Z60m Z61t Z61p 560 560Z 600 600E 600X T21 T22 T23 T41 T60p T410 T420 T520 W500 W520 R50 A21p A22p A31 A31p
NOTE: All links to PC-Doctor software hosted by me are dead. Files removed 8/28/12 by manufacturer's demand.
X22 X24 X31 X41 X41T X60 X60s X61 X61s X200 X200s X300 X301 Z60m Z61t Z61p 560 560Z 600 600E 600X T21 T22 T23 T41 T60p T410 T420 T520 W500 W520 R50 A21p A22p A31 A31p
NOTE: All links to PC-Doctor software hosted by me are dead. Files removed 8/28/12 by manufacturer's demand.
Re: RAM frequency vs. power consumption for Carolina idiots
I'm running coreboot, so yeah, it actually should handle higher clock speeds just fine. coreboot's RAM init will handle higher frequencies (and IIRC can even be made to ignore what it reads via SPD...)
But thank you, that answers my question nicely!
But thank you, that answers my question nicely!
Need help with Linux or FreeBSD? PM or catch me on IRC: I'm ThinkRob on FreeNode and EFnet.
Laptop: X270, running Fedora
Desktop: Intellistation 285 (currently dead)
Workstation: owned by my employer
Toy: Miata!
Laptop: X270, running Fedora
Desktop: Intellistation 285 (currently dead)
Workstation: owned by my employer
Toy: Miata!
-
- Similar Topics
- Replies
- Views
- Last post
-
-
ThinkPad T530 Very little power, Will not power on
by ThinkPad560X » Sun Mar 10, 2024 12:42 am » in ThinkPad T430-T490 / T530-T590 Series - 2 Replies
- 295 Views
-
Last post by ThinkPad560X
Sun Mar 10, 2024 12:57 pm
-
-
-
3 Thinkpad X31: (1) 1,6GHz, 2Gb Ram, 40Gb hdd + (2) x31 for Spare Parts + Power AC + Docking for Sale!!
by N4b00 » Mon Dec 25, 2023 7:50 am » in Marketplace - Forum Members only - 2 Replies
- 2094 Views
-
Last post by N4b00
Fri Mar 22, 2024 4:22 am
-
-
-
T520 Power Management Question
by Callahan » Wed Oct 11, 2023 7:29 pm » in ThinkPad T400/T410/T420 and T500/T510/T520 Series - 4 Replies
- 5490 Views
-
Last post by Callahan
Thu Oct 12, 2023 6:10 pm
-
-
-
A31 power button replacement.
by Gonzaleitor » Sat Oct 14, 2023 7:56 pm » in ThinkPad R, A, G and Z Series - 2 Replies
- 3253 Views
-
Last post by Gonzaleitor
Mon Oct 16, 2023 9:50 am
-
Who is online
Users browsing this forum: No registered users and 7 guests