A warning about Intel processor power consumption and high CPU usage

[Simon]

so what is the percentage usage a measure of exactly ? I used to have the impression that the processor usage was actually the usage of the FSB back in the days of sub 800MHz busses to a memory controller that then needed to talk to the memory,

Todays processors have ever more cache and ram now runs very fast. I don't really know much about the inner workings of processors but I think the initial hyperthreading was a bit of a joke. At work I switched it off and the processor noticeably performs better, possible beacause each core has more cache.

[raptor1956]

I have a pretty high end laptop with 4K LCD screen and have my Abobe suite on it so I can edit and render 4K video on it, but, laptops aren't really designed to handle heavy loading for extended periods of time and rendering 4K video could max out the PC for hours at a time.  So, although I have Premiere Pro etc on my laptop I would not use it to render a project that would require a render time more than 5 minutes or so.  To handle high workloads like longer 4K video rendering I have a desktop box with i7-5820K CPU that's water cooled and over clocked as well as a 980 Ti GPU that is also water cooled and over clocked.  Add in a PCIe SSD for OS/Programs/Scratch and a couple 6TB WD Black HD's for storage and editing and rendering 4K video is much more workable.

Choose the right tool for the job -- for prolonged heavy lifting a laptop is NOT the way to go...


Brian

[suicidaleggroll]

You can also go into the BIOS and shut off hyperthreading or turbo mode if you want.  For most tasks hyperthreading is useful, but there are some tasks where it will actually slow things down, in which case you just disable it in the BIOS and go on your merry.  There's no need to freak out about it so much.

NO I CAN'T! my bios does not have this, this is the compromise of laptops, "power" is taken away from you.

All of my laptops have this ability.  I believe it's just the low end ones that don't make basic settings such as HT and turbo mode available.

[suicidaleggroll]

If you want your laptop to run cool and quiet - don't load the CPU all day long. It's not meant to do that.

This entire thread is a head-scratcher...he's complaining about the CPU usage and power consumption when running a program whose sole purpose is to load down the processor as much as possible.  If you don't want to load down your proc, then don't run that program, it's a very simple solution.

Running processor-intensive applications 24/7 on a laptop is a horrible idea.  Not only are the cooling systems not designed for this, which will shorten the life of the electronics, but all of this extra heat will destroy the battery in short order as well.  Just don't run BOINC on a laptop or phone, it's an all-around horrible idea.

[Halcyon]

You can also go into the BIOS and shut off hyperthreading or turbo mode if you want.  For most tasks hyperthreading is useful, but there are some tasks where it will actually slow things down, in which case you just disable it in the BIOS and go on your merry.  There's no need to freak out about it so much.

NO I CAN'T! my bios does not have this, this is the compromise of laptops, "power" is taken away from you.

All of my laptops have this ability.  I believe it's just the low end ones that don't make basic settings such as HT and turbo mode available.

I have an Acer TravelMate P653 on my desk which has no CPU options in the BIOS at all. All you get are a few I/O, power saving, boot order and security options. That's it. No way to tweak memory or CPU settings. Then again it is an Acer and I'd sooner use it as a door stopper than to do any serious work on it.

If you want your laptop to run cool and quiet - don't load the CPU all day long. It's not meant to do that.

This entire thread is a head-scratcher...he's complaining about the CPU usage and power consumption when running a program whose sole purpose is to load down the processor as much as possible.  If you don't want to load down your proc, then don't run that program, it's a very simple solution.

Running processor-intensive applications 24/7 on a laptop is a horrible idea.  Not only are the cooling systems not designed for this, which will shorten the life of the electronics, but all of this extra heat will destroy the battery in short order as well.  Just don't run BOINC on a laptop or phone, it's an all-around horrible idea.

All this is true. You want a tool which is fit for purpose, not expect one device to do everything well.
I like to think of it this way: PORTABILITY, PERFORMANCE, RELIABILITY -- Pick two.

[Monkeh]

You can also go into the BIOS and shut off hyperthreading or turbo mode if you want.  For most tasks hyperthreading is useful, but there are some tasks where it will actually slow things down, in which case you just disable it in the BIOS and go on your merry.  There's no need to freak out about it so much.

NO I CAN'T! my bios does not have this, this is the compromise of laptops, "power" is taken away from you.

All of my laptops have this ability.  I believe it's just the low end ones that don't make basic settings such as HT and turbo mode available.

I have an Acer TravelMate P653 on my desk which has no CPU options in the BIOS at all. All you get are a few I/O, power saving, boot order and security options. That's it. No way to tweak memory or CPU settings. Then again it is an Acer and I'd sooner use it as a door stopper than to do any serious work on it.

Simon bought an HP. Presumably consumer-class. About six rungs down from a Travelmate!

[Halcyon]

Simon bought an HP. Presumably consumer-class. About six rungs down from a Travelmate!

Ahh yes, those consumer HP laptops are just crap. I'd put it in the same league as Acer... perhaps just a little bit more plastic.

My partner killed his HP laptop by doing nothing more than playing games on it. Granted he would spend hours with the CPU and GPU fans going at full speed. Eventually it just died. I did an autopsy and it wasn't overly dirty or clogged with dust, it just didn't survive many hours of intensive operations. As others have already pointed out, they aren't designed for this kind of torture (and it is torture). Components are stressed beyond their rated temperature limits and there is only so much a pissy little heatsink and fan is going to do (not to mention you're probably cooking the battery in the process).

[suicidaleggroll]

We have a pretty open policy at work in regards to computers.  All workstations are built by me (your basic Supermicro case/mobo + Xeon), but if someone prefers a laptop it's up to them who they go with.  Most get Lenovo or Dell business line and they all hold up very well, but a while back we had a new hire who insisted on a consumer HP laptop because it was so much cheaper with better specs.  Within a couple of months the hinges holding the screen had snapped, a few months after that the battery was dead, and by the 1 year mark it was shutting down, locking up, fan going 100% for no reason at all...basically unusable.  He now knows why they're so cheap.

[Twoflower]

If the OS says 100% it means it cannot utilize more execution units in the CPU. So that's for the end-user the correct reading. No, not even in the FSP times it was the CPU-Load. It is generated by the CPU performance counters. I haven't looked in the exact way what the CPU counts, but it could be the ratio of clock cycles were at least one execution unit is busy over the total number of clock cycles.

I think the current core designs are better in several cases. One big improvement might come from the number of execution units and the ability to feed them (here you see them for a single Skylake core, the ones in your cpu). But even then some codes run better without HT others with. Especially with a low number of cores and an interactive machine (you would like to work on your laptop) probably the system 'feels' more responsive with HT is enabled. Even if the throughput of BOINC suffers a bit.

By the way: If you limit your software (in your case BOINC) to start so many threads as your CPU has physical cores (in your case 2) you should see some OS-Magic: The HT-Cores get into the 'Parked' state. They won't get used except a new thread appears then a parked core will get activated.

One more point: As I said I used to run Seti@home a lot. And I think I killed some 2.5" hard drives of my laptop back then by doing so. The ones installed in laptops are not nearly designed to operate 24/7. More like 8h/day. And the cooling fan won't live forever too.

(Wow! 7 new posts while writing this post!)

[mmagin]

Realistically, all laptops are a compromise in terms of power and thermal management.  (With the exception of some huge models made from basically desktop parts.)  If you want something that basically never throttles for thermal or power consumption reasons, use a desktop/server.  (And even there maybe some minor things you cannot disable.)

[Simon]

If you want your laptop to run cool and quiet - don't load the CPU all day long. It's not meant to do that.

This entire thread is a head-scratcher...he's complaining about the CPU usage and power consumption when running a program whose sole purpose is to load down the processor as much as possible.  If you don't want to load down your proc, then don't run that program, it's a very simple solution.

I think my point is pretty obvious. I don't mind using power but the concern is the watt per gigahertz of processing. I don't want to use 66% more power for a mere 24% gain in speed. The laptop was advertised as having a 2.5 GHz processor the increase in speed while welcome is gained at a horrendous increase in power consumption. Given that I'm reasonably clever I have looked into this and worked out how to get the laptop to not go over a certain speed and remain efficient and not generate too much heat. From there I can run BOINC at any setting I choose which could be 100% or it could be less so that I don't as you say over stress the laptop. This was not about power consumption per se but actual efficiency of the system. The headline figure is 2.5 GHz, I never asked for 3 GHz or 3.1 GHz. I also don't mind loading down the processor as BOINC does a fairly good job of keeping out of my way and given the hyper- threading technology it will if I'm not running two tasks per physical core help with the overall system responsiveness.

[Simon]

Simon bought an HP. Presumably consumer-class. About six rungs down from a Travelmate!

It's a HP 250 G5 I have no idea what class it is. It cost me 690 pounds although this was after the upgrade of the hard drive to a solid state and the putting of the correct amount of RAM into the laptop filling both slots because what these bastards do is sell you a laptop boasting dual channel memory when only one slot is filled. I bought it off a guy on eBay so I have no idea what the original laptop cost I think he buys them you up specs them and sells them on. Since I pointed out that I didn't want to cancel my order with him when he told me he could not give me a VAT receipt because I couldn't get the same thing elsewhere anyway even without the VAT he has stuck his price is right up and now wants nearly 800 pounds for the same laptop. As I have said before it is a pretty good machine and has easy replace my quad core bulldozer processor which runs just over 4 GHz with DDR three RAM at 1.8 GHz in my desktop.

[Simon]

We have a pretty open policy at work in regards to computers.  All workstations are built by me (your basic Supermicro case/mobo + Xeon), but if someone prefers a laptop it's up to them who they go with.  Most get Lenovo or Dell business line and they all hold up very well, but a while back we had a new hire who insisted on a consumer HP laptop because it was so much cheaper with better specs.  Within a couple of months the hinges holding the screen had snapped, a few months after that the battery was dead, and by the 1 year mark it was shutting down, locking up, fan going 100% for no reason at all...basically unusable.  He now knows why they're so cheap.

Unfortunately for what I wanted I didn't get much choice. There are a few laptops out there boasting DDR for memory with a HD screen. My previous laptop was a relatively cheap zoo storm one and has been dragged around for a few years and not particularly treated very well and it held up just fine. The processing probably used about as much power if not more than this laptop and it also ran BOINC at 100% for prolonged periods. I only gave it up because I realised the screen was crap, not only was it low resolution but the actual spacing between the pixels was very visible and was making my eyes hurt. When a bit richer I could probably afford a high-end laptop. But this is all I could afford.

[Simon]

By the way: If you limit your software (in your case BOINC) to start so many threads as your CPU has physical cores (in your case 2) you should see some OS-Magic: The HT-Cores get into the 'Parked' state. They won't get used except a new thread appears then a parked core will get activated.

One more point: As I said I used to run Seti@home a lot. And I think I killed some 2.5" hard drives of my laptop back then by doing so. The ones installed in laptops are not nearly designed to operate 24/7. More like 8h/day. And the cooling fan won't live forever too.

Yes indeed I only have two cores enabled for BOINC. It was actually a pleasure to hear somebody advertising and I seven processor with the correct specification. It was advertised as a 2 core machine not a four core as most of the big retailers would. As I said before as far as I am concerned BOINC can use the maximum of the physical cores available and the virtualisation can help with responsiveness. Now with my work computer it is more responsive if I turn a hyper threading off but that is quite an old machine and the technology might not be as good as it is now.

[Monkeh]

Unfortunately for what I wanted I didn't get much choice. There are a few laptops out there boasting DDR for memory with a HD screen

Yes, very few. Merely all of them.

It was advertised as a 2 core machine not a four core as most of the big retailers would.

Y'know, I've had a quick look around and haven't seen anyone advertising a 6500U as quad core.

[NottheDan]

Unfortunately for what I wanted I didn't get much choice. There are a few laptops out there boasting DDR for memory with a HD screen

Yes, very few. Merely all of them.

Are there even any HD screen laptops with only DDR RAM? I thought the switch to DDR2 had already been completed when HD screen came on the market.

[Monkeh]

Unfortunately for what I wanted I didn't get much choice. There are a few laptops out there boasting DDR for memory with a HD screen

Yes, very few. Merely all of them.

Are there even any HD screen laptops with only DDR RAM? I thought the switch to DDR2 had already been completed when HD screen came on the market.

Oh, probably. But I was thinking of DDR as a general technology, not the first gen specifically..

I think he meant DDR4, actually, in which case.. he got lied to, because his laptop uses DDR3.

[Simon]

Unfortunately for what I wanted I didn't get much choice. There are a few laptops out there boasting DDR for memory with a HD screen

Yes, very few. Merely all of them.

Are there even any HD screen laptops with only DDR RAM? I thought the switch to DDR2 had already been completed when HD screen came on the market.

HD in laptops still comands a premium, what I am saying is that to get HD AND the latest processor/ram cost that bit more.

[Simon]

Unfortunately for what I wanted I didn't get much choice. There are a few laptops out there boasting DDR for memory with a HD screen

Yes, very few. Merely all of them.

Are there even any HD screen laptops with only DDR RAM? I thought the switch to DDR2 had already been completed when HD screen came on the market.

Oh, probably. But I was thinking of DDR as a general technology, not the first gen specifically..

I think he meant DDR4, actually, in which case.. he got lied to, because his laptop uses DDR3.

I think the name has been used over and over again by HP, I also found nothing specific when looking my model up. SANDRA reports:

SiSoftware Sandra

Computer
Manufacturer : HP
Model : HP 250 G5 Notebook PC
Family : 103C_5336AN G=N L=SMB B=HP S=250
Version : Type1ProductConfigId
Serial Number : CND63*****
ID : 7110666B-E6115667******************
SKU Number : X0N34EA#ABU

Chassis
Manufacturer : HP
Type : Notebook
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Version : Chassis Version
Power Cord(s) : 1
Serial Number : Chassis Se***********
Asset Tag : Chassis Asset Tag
Boot-up State : Safe
Power State : Safe
Thermal State : Safe
Security State : External Interface Locked-out

Mainboard
Manufacturer : HP
Multi-Processor (MP) Support : No
Model : 81EB
Type : Mainboard
Version : 61.30
Serial Number : PFXPQI2*******
Asset Tag : Type2 - Board Asset Tag
Location in Chassis : Type2 - Board Chassis Location

Mainboard Properties
Removable : No
Replaceable : Yes
Hot Swap : No

On-board Devices
IGD : Video Adapter (Disabled)
Hanksville Gbe Lan Connection : Ethernet Adapter (Enabled)
Other : Other (Enabled)
3165NGWG : Other (Enabled)

Chipset
Model : HP Core (Skylake-U) ULV Host Bridge/DRAM Registers
OEM Device Name : Intel Core (Skylake-U) ULV Host Bridge/DRAM Registers
Revision : A9
Bus : Intel CSI (Quick Path)
Front Side Bus Speed : 100MHz
Width : 20-bit / 20-bit
HTT - Hyper-Threading Technology : Yes
Maximum Bus Bandwidth : 400MB/s
Maximum Power : 3.400W

Features
VT-d - Virtualisation Technology : Yes

Chipset 1 Hub Interface
Type : DMI (Direct Media Interface)
Version : 1.00
Multiplier : 0x

Logical/Chipset Memory Banks
Bank 0 : 8GB SO-DIMM DDR4 15-15-15-36 4-51-17-9 3T
Bank 2 : 8GB SO-DIMM DDR4 15-15-15-36 4-51-17-9 3T
Shared Memory : 770MB
Maximum Memory : 32GB
Supported Memory Types : DDR3 SO-DIMM DDR4
Channels : 2
Width : 128-bit
Memory Bus Speed : 2x 1GHz (2.13GHz)
Multiplier : 32/3x
Integrated in Processor : Yes
Maximum Memory Bus Bandwidth : 33.34GB/s

Memory Module
Manufacturer : Samsung
Model : M471A1G43DB0-CPB
Serial Number : 9812****
Type : 8GB SO-DIMM DDR4
Technology : 8x(4096Mx8)
Speed : PC4-17100SO DDR4-2132
Standard Timings : 15-15-15-36 4-51-16-5
Interface : 1.00
Memory DC Line : 1.200V
Temperature Sensor(s) : No
Timing @ 1164MHz : 16-16-16-38 4-54-17-6
Timing @ 1091MHz : 15-15-15-36 4-51-16-5
Timing @ 1018MHz : 14-14-14-34 4-48-15-5
Timing @ 945MHz : 13-13-13-31 3-44-14-5
Timing @ 873MHz : 12-12-12-29 3-41-13-4
Timing @ 800MHz : 11-11-11-26 3-37-12-4
Timing @ 727MHz : 10-10-10-24 3-34-11-4

Memory Module
Manufacturer : Samsung
Model : M471A1G43DB0-CPB
Serial Number : 980F****
Type : 8GB SO-DIMM DDR4
Technology : 8x(4096Mx8)
Speed : PC4-17100SO DDR4-2132
Standard Timings : 15-15-15-36 4-51-16-5
Interface : 1.00
Memory DC Line : 1.200V
Temperature Sensor(s) : No
Timing @ 1164MHz : 16-16-16-38 4-54-17-6
Timing @ 1091MHz : 15-15-15-36 4-51-16-5
Timing @ 1018MHz : 14-14-14-34 4-48-15-5
Timing @ 945MHz : 13-13-13-31 3-44-14-5
Timing @ 873MHz : 12-12-12-29 3-41-13-4
Timing @ 800MHz : 11-11-11-26 3-37-12-4
Timing @ 727MHz : 10-10-10-24 3-34-11-4

Sensor
Model : Hewlett-Packard  PABAS0241231 BAT
Mainboard Specific Support : No

Sensor
Model : Intel Core CPU [P1, C2, T7]
Version : 78.03
Mainboard Specific Support : No

Temperature Sensor(s)
CPU Temperature : 39.00°C

Voltage Sensor(s)
CPU DC Line : 0.897V
Battery DC Line : 17.028V

Capacity Sensor(s)
UPS/Battery Capacity : 40.61Wh

System Bus(es) on Hub 1
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System Bus 0 : PCI
System Bus 1 : PCIe 3.00 x1 2.5Gbps
System Bus 2 : PCIe 3.00 x1 2.5Gbps

LPC Hub Controller 1
Model : HP Sunrise Point-LP LPC Controller
OEM Device Name : Intel Sunrise Point-LP LPC Controller
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ACPI Power Management : No
Advanced TCO Mode Support : No
RNG - Random Number Generator : No

Disk Controller
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OEM Device Name : Intel Sunrise Point-LP SATA Controller [AHCI mode]
Interface : SATA
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Disk Controller
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Audio Device
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OEM Device Name : Intel Sunrise Point-LP HD Audio
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USB Controller 1
Model : HP Sunrise Point-LP USB 3.0 xHCI Controller
OEM Device Name : Intel Sunrise Point-LP USB 3.0 xHCI Controller
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Supported Speed(s) : Full (12Mbps) High (480Mbps) Super (4.8Gbps)
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SMBus/i2c Controller 1
Model : Intel ICH SMBus
Version : 2.01
Specification : 2.00
Advanced TCO Mode Support : Yes, Disabled
Slave Device Enabled : Yes
PEC Support : Yes
Speed : 100kHz

Expansion Slot(s)
J6C1 (1h) : PCIe x1 PME Hot-Plug Used
J6D2 (2h) : PCIe x1 PME Hot-Plug Available
J7C1 (3h) : PCIe x1 PME Hot-Plug Available
J7D1 (4h) : PCIe x1 PME Hot-Plug Available
J8C1 (5h) : PCIe x4 PME Hot-Plug Available

Port Connector(s)
J1A1 - Keyboard : Keyboard / PS/2
J1A1 - Mouse : Mouse / PS/2
J2A1 - TV OUT : Video / Mini-DIN
J2A2 - CRT : Video / DB-15 pin female
J2A2 - COM 1 : Serial Port 16550A / DB-9 pin male
J3A1 - USB : USB / USB
J3A1 - USB : USB / USB
J3A1 - USB : USB / USB
J5A1 - USB : USB / USB
J5A1 - USB : USB / USB
J5A2 - USB : USB / USB
J5A1 - Network : Network / RJ-45
J9G2 - OnBoard Floppy Type : Floppy Disk
J7J1 - OnBoard Primary IDE : ATA
J30 - Microphone In : Audio / Mini-jack
J30 - Line In : Audio / Mini-jack
J30 - Speaker Out : Audio / Mini-jack
Ctrl0Port0 - Primary HDD Bay* : SATA
Ctrl0Port1 - Secondary HDD Bay* : SATA

Performance Enhancing Tips
Warning 2542 : Memory bus speed exceeds Chipset rated speed. Reduce FSB/memory multiplier.
Warning 2513 : TPM not detected. Some security features are unavailable.
Tip 2 : Double-click tip or press Enter while a tip is selected for more information about the tip.

[Simon]

Unfortunately for what I wanted I didn't get much choice. There are a few laptops out there boasting DDR for memory with a HD screen

Yes, very few. Merely all of them.

It was advertised as a 2 core machine not a four core as most of the big retailers would.

Y'know, I've had a quick look around and haven't seen anyone advertising a 6500U as quad core.

Glad to hear it, maybe the marketing fad has died out. Look out on ebay though, you can get a 10GHz processor........ (4x 2.5GHz processor when it is actually a 2 core.....)

[Fsck]

Modern processors have sleep states to save power when the user isn't doing much, and burst frequency states for work.
I don't understand why you're complaining.
The goal is to zip a file or something really quickly using a high frequency state, do whatever else you want, then go back to sleep and not have the user wait on a more efficient processor doing it slowly.

Excessive power use at high frequency has been known for quite a while... since the preshot pentium 4 days afflicted everyone.
This fact has forced people to seek more parallelism. Top of the line Xeon processors for pure compute can give you 22 cores of 2.2GHz at 135W TDP at a hilarious price tag.
If heavy compute isn't needed, the Xeon D-1541 for 8 cores of 2.1GHz at 45W is pretty popular for storage and network appliances.
250-400$ USD can net you a v3 Haswell ES 10-14core processor which will stomp a laptop chip into the ground. (you'll likely have to pay more for a board for it)

Why are you running a continuous heavy compute workload on a "U"-type processor anyways?

The i7-6500U is skylake and not really that old. People are building "new" rigs, on older Haswell ES xeons these days quite commonly. It's successor, the i7-7500U is kaby lake, released in sept 2016, a pretty recent update considering the state of the CPU industry.

[Monkeh]

So they come in both DDR3 and DDR4, how fun.

As for the screen.. You don't need 1080p to be classed as 'HD'. And as for <1080p.. only for the cheap trash!

The SSD is standard HP spec, and that spec is £500 with a little hunting.

[Someone]

I think my point is pretty obvious. I don't mind using power but the concern is the watt per gigahertz of processing. I don't want to use 66% more power for a mere 24% gain in speed.

But how have you measured this? The power scaling will be faster than the performance as the voltage also adjusts up with frequency. Perhaps you've just found a local minima on the power/performance curve from the limited number of steps the voltage is adjusted in.

The fans turning on is annoying from your perspective, but they are unlikely to be very linear with power consumption. The modern core processors will turn of inactive cores and can happily churn away on a single core turbo with surprisingly low power, its when all cores are powered up that the consumption peaks. Trying to game processor affinity is a losing battle when most of the threads will be memory throttled, in general leave the OS to work its magic as it will do better than you can. The only thing left is to finesse the power management to suit your desire of keeping the voltage scaling down, but you'll need to experiment with the workload difference between using just a single thread and powering multiple cores.

[TechnicalBen]

On the desktop, i3 were single and dual cores, i5 were quad core, i7 were quad and more cores.  Like you, I am not really into i7, I would have to pull up wiki to find out what exactly difference is between i5 and i7.

I don't know what the difference between the i3, i5 and i7 are, but I suspect the power profile is the same on all as it is common across processors, more speed = more heat, so for more speed more voltage is required.

It use to be that i7 were still only quad cores, but had the "hyperthreading". Which is more about instruction ques and making use of the entire core, and not letting it go to waist. It does not give you twice the performance or twice the core power/speed/processing. In some tasks, it gives better speed, in others it gives slightly less (due to the wait while it checks to see if it should use hyperthreading or default to using just one instruction).

My terminology may be completely off there. But it's a complex pipeline, it's late at night, and I really should read up on it again. But as an example, think of it as putting a divider in the middle of each seat in your sports car. You can now take twice as many half sized people, but you get to the destination in the same time, same speed, snd no quicker than before. You cannot take more mass than before, your seats are the same size, and normal sized people may find the dividers uncomfortable when getting in.

macboy gave the proper and fully correct description! I'll have to work on an example with people getting in and out a not full up bus.

You can turn  HT off on some motherboards, as when doing certain compute tasks it may give a slight advantage to turn it off.

[Simon]

I think my point is pretty obvious. I don't mind using power but the concern is the watt per gigahertz of processing. I don't want to use 66% more power for a mere 24% gain in speed.

But how have you measured this?

um the manufacturers own published data ? they say 2.5GHz 15W which is what it is sold at and turbo mode of 3.1GHz 25W except that it will sit happily at nearly 3GHz non stop so not sure if it's meant to do that but windows allows it.