Explain to me notebook power consumption (watt/amp/TDP)

without going into the "just buy a new laptop" discussion, im looking to upgrade my msi gx630, and had concerns over power consumption.

In this thread im not concerned with battery life or proper cooling at all. I want to know where my wattage and amperage limits are going to be.

Question1: does TDP translate to ACTUAL watt usage? (assuming full load)
Question2: what determines a sytems max watt/amp... battery? power adapter? both? something else?

I come from a very heavy desktop background so i have basic knowledge on the functions of power supplies i.e. ac>dc, total watt of system, amps per rail, etc. However, some of these manufacturers specs have me scratching my head.

FOR EXAMPLE: (these are TDP numbers so question 1 may clarify this)
MSI GX630 = 25wCPU 23wGPU with a 120w power adapter
MSI GT627 = 25wCPU 60wGPU with a 90w power adapter???

im confused, i just want to know if i were to put a 35wCPU and a 60wGPU if my system would have stability issues not with heat but with lack of power

 

i can already see its going to happen with the MSI GT627, lots and lots of in-warranty dead power supplies. running a max draw only 5w less than its capable will kill it pretty quickly, and it will get roasting hot.

anyway, to try and answer your question, The internal mechanisms of a laptop will of course be able to sufficiently power all the components without any additional cooling strictly necessary, or reductions in performance or stability. the only problem i see with either of them is the GT627, as mentioned in my above comment.

 

I can't fully answer your questions, but I'll share what I DO know (or think that I know, that is)!

TDP (Thermal Design Power) is the the maximum amount of power that the cooling system must be able to dissipate. (Power = heat)

For example, Intel's P-series (P7350, P8400, etc.) have a TDP of 25W compared to most standard Intel Core 2 Duo processors with TDP of 35W. The TDP (25W/35W) is the the maximum amount of power that the cooling system is capable of dissipating the heat generated at the respective TDP rating. Under most conditions, processors aren't running at 100%, so the difference between 25W and 35W processors may not be significant in normal use.

Here are two articles on TDP- LINK and CPU power dissipation- LINK

 

i hear ya, so to my understanding the TDP is SIMILAR to the speed rating of of a processor in that say the manufacturers speed is rated at 4800 whereas the actual mhz is say 2.4ghz

the same applies to the tdp??

so say a zm-86 had a TDP of 35 that doesnt mean that it ACTUALLY consumes 35w it may only consume 30

sooooo if i did understand that correctly then TDP helps me in no way decide if i have adequate power lol

 

AMD and Intel have totally different measurements towards TDP.

If a notebook comes with a 90W power supply, the manufacturer will be sure that it will be fully powered, even at the max stress testing of every component simultaneously.

How you can measure roughly what your power consumption is, is by knowing the battery capacity (WHr) and seeing how much battery life you get. If you stress both CPU and GPU and your battery dies in 1 hour on a 60WHr battery, then your max consumption is about 60W.

 

a great example are the desktop graphic cards. some cards consume like 250Watts. of course they just spend that large amount of energy under heavy load. most of the time they just spend a fraction of it. otherwise the power bill would be astronomical.
you should also be concerned about heat.

 

Benchmarks scores and, to some degree, TDP ratings are a lot like 0-60 figures for a car. It's one measure of performance, but it's the fastest time possible. In daily driving, you won't be duplicating that figure very often (due to traffic, speed limits, etc). It's rare that a dual-core processor runs at 100% for extended periods of time.

It's also my understanding that Intel's TDP represents the maximum cooling capacity that the system can handle for a sustained period. For example, 35W TDP = 'X' amount of heat requiring dissipation. However, it's possible that the system could peak higher than 35W actual consumption.

I'm not sure if this helps or makes things more confusing?

Other components have a TDP rating, such as the chipset. For instance, the Intel GL40/GM45 (including integrated graphics) has a TDP of 12W, while the PM45 (not including the dedicated video card) has a TDP of 7W.

As for power supplies, Dell usually includes a 65W AC Adapter on models with integrated graphics and a 90W AC Adapter one models with a discrete GPU.

 

its making sense dont worry, im sorting it out.

sgogeta, i found out that the battery on the gx630 is 51.84Whr and at full load would probably drain the battery in about the same number of minutes, probably a few less, so im going to say the consumption is somewhere around 60w.

So does the ac adapter determine the maximum watts? or does the battery? this is another thing that confuses me.

Say i have a desktop with a 500w PS i know the maximum amount of watts that PS can deliver is 500w assuming 100%eff which doesnt happen i know.

but with a laptop i have 2 seperate sources of power. Does the battery have a maximum wattage output, or does it just use whatever it wants? OR does the ac adpater control the max watt?

does that mean if i have a 120w ac adapter and im using roughly 60w i have another ~60w to play with?

 

1.TDP does not nessarily translate to real energy use. There's no such thing as Wattage use. Watt = I*V (current *voltage). W= (N*J)/s as well ( i think).

AMD processor rates their TDP sort like average power consumption
Intel processor rates their TDP as maximum power used
I'm not sure about the graphic card's TDP rating though.

2.The real powersupply integrated on your motherboard is the real limit. The battery and the powersupply usually is not the limit unless the battery is charging while comptuer is running, power brick might limit the power draw.

3. MSI GX630 = 25wCPU 23wGPU with a 120w power adapter
MSI GT627 = 25wCPU 60wGPU with a 90w power adapter

One laptop simply has highier power rating power brick. The power brick is like your ATX powersupply in your desktop. It'll only take/give just enough power to your laptop. Typically, the power brick is switching type thus the same as standard ATX PSU except the power efficiency is much much lower. The powerbrick is responsible for converting AC-> DC. The real power supply is inside your laptop which converts the preconverted DC to different voltages split into many rails. Basically, a laptop's powersupply is broken into 2 parts, the power brick and the power supply.

using a 120W power adapter simply means you can charge the battery faster. Also sometimes, a a computer drawing 60W from a 120W power brick is more efficient than drawing 60W from 90W power brick. It might also be the other way around so there's no definet anwer.

4. You should be fine with a 30W + 60W GPU.

The battery isn't 100% efficient either. It's probably in the ball park of 50-75% efficient. Depending on the temperature, internal resistance might increase or reduce thus providing "more power" and the battery should last longer. Good luck applying the "Law of Conservation of Energy" to this example. LOL There are many factors which determines the battery life of Li-ion battery.
Typically, when your Li-ion battery says it's 60WHr, it can probably store at least 150-200Whr of energy, but you can only use more or less around 60WHr depending on the operating condition.

 

houston we have liftoff

thank you sir, that would answer my question

 

Hopefully we don't have SNAFU in the future launches. LOL