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T400/W500 - Enormous idle consumption on dedicated graphics
Posted: Sat May 24, 2014 1:54 pm
by Andrew479
Hi there,
for a long time I thought it's just normal function of HD3000 series to be totally power inefficient, however after reading several reviews on T400 and T500 (W500) I came to conclusion that something is wrong.
My new
T400 drains about 16W in dedicated mode just by idling and 'sitting totally still',
W500 even 18W.
T400 uses HD3470 core, which is rated 12W TDP, nevertheless at full load, whole laptop has 35W <- that's WAY too much for this specs
W500 uses HD3650 core which is rated 30W TDP, on full load whole laptop consumes 60W
There's something wrong with those numbers, idle power usage as reported by various reviews should be 2-3W above integrated 4500MHD, however in my case it's
8-11W
In this situation the notebook is only consuming roughly 8.5 watts of power. In dedicated graphics mode under the same settings battery life falls by exactly 2 hours down to 7 hours and 41 minutes, and power draw increases to 10.5 watts. The 6-cell battery managed 6 hours and 4 hours and 28 minutes respectively.
Source:
http://www.notebookreview.com/notebookr ... 00-review/
The power consumption shows that the Thinkpad T500 consumes about 3.5W less energy with the integrated graphics card, compared with the dedicated ATI graphics card. The lower energy consumption of the integrated chipset is also noticeable under load.
Source:
http://www.notebookcheck.net/Review-Len ... 970.0.html
In dedicated graphics mode, the screen brightness set to 60%, and wireless active the T500 managed 5 hours and 6 minutes before it shut itself down at 5% remaining. Even though it is still way under the T400 by a couple of hours, it is still very impressive for a 15" notebook. In integrated grahics mode with the same settings, the system squeezes out an hour and a half more, bringing the average consumption from about 13 watts down to 11 watts. The 9-cell battery gives you more than enough time to watch a movie or two on a flight, or even get some work done.
Source:
http://www.notebookreview.com/notebookr ... ad-review/
T500 = W500 - only difference is WUXGA+ and unlocked V5700 GFX
What am I doing wrong??
OS in both cases: Win7 x64 with latest Power Manager, bios 3.25 dated 2012-12-07 and official ati drivers from Lenovo.
Wi-Fi disabled, single memory module, screen always at minimum brightness
Please somebody reply, this issue has been bothering me for many months and was the reason for me to buy T400 (which has the same issue apparently)
Thank you in advance
Re: T400/W500 - Enormous idle consumption on dedicated graph
Posted: Sat May 24, 2014 2:29 pm
by precip9
I don't have my W500 open right now, but I recall a specific ATI setting, accessible from
Control Panel->PowerOptions->Edit Plan Settings->Change advanced power settings
with the typical choice of prioritizing power or performance.
Re: T400/W500 - Enormous idle consumption on dedicated graph
Posted: Sat May 24, 2014 2:52 pm
by Andrew479
Yep I forgot to mention PowerPlay - it's on "maximum battery saving"
CPU is running at its lowest voltage (0.875V) and lowest non-LFM multiplier - 6x - 1600MHz
Same thing

Re: T400/W500 - Enormous idle consumption on dedicated graph
Posted: Sat May 24, 2014 4:29 pm
by RealBlackStuff
AFAIK it's not the graphics GPU, but the CPU that sucks power.
Put in a Pxxxx CPU instead of a Txxxx and save energy!
Re: T400/W500 - Enormous idle consumption on dedicated graph
Posted: Sun May 25, 2014 1:28 am
by Andrew479

LOL! Good one.
Actually NO. CPUs are P8700 and P9500, both are undervolted and underclocked and consume max. 12W which is way below their specs. And that's not how CPU would behave anyway, nor it would make any sense - the temps are pointing to the GFX.
Let me repeat what I said in the first post - the difference between idling at integrated vs. dedicated is not 2-3W but 8-11W:
On integrated both laptops idle at 6W
On dedicated both laptops idle at 15-17W
So that rules out CPU
My tips would be:
- driver error for PowerPlay GPU frequency scaling - use different scaler (Atitool, ...)
- BIOS - might be fixed by downgrading
- OS related driver issue - those reviewers might have tested it under Vista
- if somebody could send me working ROM captured through ATIWinFlash for HD3470 and V5700 <- however it doesn't look like ROM issue, since it happened on two different laptops
I'm going to try these, then I'll report back

Re: T400/W500 - Enormous idle consumption on dedicated graph
Posted: Sun May 25, 2014 4:13 am
by 600X
I think I know where the problem lies. TDP stands for thermal design power, and has little to do with the actual power consumption. The TDP stands for the heat that can be produced and is merely a guideline for manufacturers so they know what kind of cooling system they will need.
If a chip has a TDP of 10W, it doesn't actually mean that it will consume a max. of 10W of powers, it can consume less or more.
Re: T400/W500 - Enormous idle consumption on dedicated graph
Posted: Sun May 25, 2014 4:39 am
by Andrew479
Again no, thermal design power is just what you explained but it has nothing to do with current issue.
Third recap: Why is idle power consumption on dedicated graphics higher by significant amount than reviewers, manufacturers and just about any average user stated?
Let's try different approach:
Those of you who possess T400/T500/W500, can you switch on dedicated graphics and write here your watt figure?
Or perhaps just an estimate how long your machine will last on ATi GFX?
BTW, BIOS and Driver rollback didn't help.

Tried going through 'average user' route - Thinkvantage System Update -> no dice
Re: T400/W500 - Enormous idle consumption on dedicated graph
Posted: Sun May 25, 2014 4:49 am
by 600X
Sadly, I just sold my T500 with ATI, otherwise I would've checked. But I remember it being able to become very hot in idle with the ATI activated. But perhaps a different question: Why would you want to use the dedicated graphics in idle/desktop mode? Usually you would activate it when playing games and stuff like that, in which case the power consumption would be at max. anyway, so it doesn't really matter. Or do just want to figure out what's "wrong"? (if anything at all is wrong)
While I can't check my T500 anymore, I do recall its idle power consumption with integrated graphics to be well above 10W and coming close to or exceeding 20W with the ATI enabled.
I had a P8600 and Intel SSD installed, along with Win 7 and all necessary drivers. BIOS was probably the latest version, though I don't remember. Brightness was usually set to 13/15, I had a SHARP WUXGA display. (Dell OEM part)
I'd usually get about 2h of battery life from a 40Wh battery on integrated graphics.
Re: T400/W500 - Enormous idle consumption on dedicated graph
Posted: Sun May 25, 2014 4:59 am
by Andrew479
Those are just about the figures I'm getting - about 20W on that brightness being sitting duck.
The reason for me is simple - efficiency.
4500MHD is not really optimized for 3D games no matter their requirements, a dedicated alternative should consume even less power than integrated as it's optimized for 3D calculations where 4500MHD would struggle using its raw processing power. This would enable efficient operation when performing 3D calculations on battery power.
Also discrete ATis have DVI/DisplayPort capability, which really comes in handy.
10W is really some difference and even for desktop usage, it would unnecessarily heat up the laptop. Even my desktop PC graphics does not consume that much when idle (HD7750 consumes about 3W, whole desktop then 21W)
My W500 successfully fried one battery back, e.g. its thermal fuse (I made a topic about it some time ago).
X1400 on my now sold R60 idled at 1-2W so the whole laptop idled at 7W with screen off and that was 90nm technology.
So now everything points to used OS (W7 vs. Vista)
UPDATE: Removed modem daughter card and wi-fi - consumption dropped by 1.5W
In that case I'll remove the bluetooth as well, never using wireless anyway (health risk)
And if needed one can use USB BT/WiFi
With integrated graphics, T400 now idles at 5.5W
However still delving into ATi issue, PowerPlay has 3 modes, lowest clock is at 265MHz core at 0.9 VDDC and that seems engaged.
Without PowerPlay core voltage is 1.2V and consumption rise by 5W.
To me, it seems like the GFX can't put itself to sleep mode. Perhaps faulty VBIOS? Unlikely but possible
Re: T400/W500 - Enormous idle consumption on dedicated graph
Posted: Sun May 25, 2014 3:07 pm
by Medessec
Well, keep in mind that the distinctive difference in power consumption is mostly owing to the fact that when the Integrated-graphics mode is activated, most if not all functions and hardware related to the GPU are shut off. The 4500HD Integrated is "on", even in dedicated graphics mode, because it's part of the Intel chipset. Functions and some aspects of video output still have to use it, simply because of Intel's design. When the ATI card is switched off, the entire ATI side of things is completely deactivated, and the Intel graphics chipset takes over the whole load of video output.
So it wouldn't surprise me that the laptop needs an extra 3 Watts of power, just to have an ATI chip turned on. It's kinda like the Wi-Fi card problem in the X60/X61 laptops, the only way to keep the palmrest from getting scalding hot is not to "not browse the web" or "disconnect from your router", you have to use the Thinkpad's hard-radio toggle(the Wi-Fi switch) to completely disable the Wi-Fi card. Because even if it's just sitting there doing nothing, the BIOS, OS, and other software are forced -by code- to poke the device every one thousandth or whatever a second: "Hey Wi-Fi card!", "I'm not doing anything.", "Oh." *CPU cycle* "Hey Wi-Fi card!" ...rinse repeat.
Modern integrated graphics and dedicated solutions side-by-side have gotten a lot better... especially laptops with NVIDIA Optimus. The A-series AMD CPUs(although I hate to admit it) are absolutely crazy good too- my friend had an AMD APU A10-4600M HP DV7(which has since broken); him and I played a really high-quality graphics FPS video game for nearly 4 hours, and he didn't know his laptop was on battery until his screen blacked out while he was playing(his laptop was hibernating.) 3 hours, of heavy-load video gaming, on battery. Wow.
The T400/T500 were probably one of the earliest examples of a laptop with Integrated graphics and dedicated graphics side-by-side in the same machine, switchable to the user's discretion. It works very well, but it doesn't surprise me at all that it's not the most efficient solution around.
Oh god- nearly forgot to mention it. I mentioned my friend with the HP DV7 that broke: A total case of irony with this particular discussion, he ended up getting a Thinkpad from me to replace it. What Thinkpad did he get you might ask?
A W500.

Re: T400/W500 - Enormous idle consumption on dedicated graph
Posted: Sun May 25, 2014 3:35 pm
by Andrew479
You know, 3 watts would be totally OK by me, as I am trying to say this whole thread. However 10W is way too much.
And even if iGFX is "on", it shouldn't have any measureable impact on consumption.
If that was true, then how come HD3470 equipped laptops such as disassembled Acer on my workplace doesn't consume as much when idle? It's equipped with P8600 which does have embedded iGFX in it.
The whole scenario just doesn't make sense, especially when some people clearly reported 10.5W on T500. It would really help if somebody (please finally!) would be so kind and report us their values and what OS are they using.
Of course most remotely controlled electrical devices use some power even when not active (it's called stand-by power consumption)
Re: T400/W500 - Enormous idle consumption on dedicated graph
Posted: Tue May 27, 2014 3:52 am
by Medessec
It would really help if somebody (please finally!)
My roommate has a T500 I can probably check- although I'm visiting parents, so someone may beat me to it.
Yes, it's an ATI model. It's a T500 with a WSXGA+ screen, and the HD3650 switchable.
What method are you using to measure wattage consumption? An external watt-o-meter at the plug, or software?
Re: T400/W500 - Enormous idle consumption on dedicated graph
Posted: Tue May 27, 2014 4:13 am
by Andrew479
OK, thanks a lot.
Wattage is measured both ways - software through Power Manager and RMClock and also amperage on 20V input, lastly thermal dissipation of the ATi card (though that's rather an estimation).
Measuring amperage on 230V IN would be very inaccurate due to power supply's average efficiency (80%).