M4800 Owner's Thread

Just my two pennies: I don’t think this could possibly help anyhow…
NMP, though.

 

Doesn't work. On A07+, when you plug in an adapter of under 150W, the upper speed bins simply cease to exist. The CPU will report an abbreviated or single entry Speedstep table. See examples:

Normal, 180W+ on any firmware:
1. 800MHz 2. 900MHz 3. 1000MHz etc etc etc etc 51. 3600MHz 52. 3700MHz

On 120W adapter and firmware A06:
1. 800MHz 2. 900MHz 3. 1000MHz etc etc etc etc 41. 3100MHz 42. 3200MHz

On 90W adapter and firmware A06:
1. 800MHz 2. 900MHz 3. 1000MHz etc etc etc etc 31. 2600MHz 32. 2700MHz

On anything <150W on A07+:
1. 800MHz (THE END)

I've run other adapters on A06, and it shows DIFFERENT speedstep/turbo boost behavior, so Dell can't claim they never supported anything but 180W+. They'll try, but it's a flat out lie. They intentionally removed all the profiles that handle <180W in firmware A07 and have not fixed it since. This makes firmwares A07+ completely unusable for me. I have a 240W adapter on my work docking station, and a 180W adapter on my dock at home, but I have 120W adapters in various places around the house, and I keep a few extras for travelling. With A06, the laptop runs fine on 120W, Optimus works, the CPU even turbo boosts, it's completely stable. There is very clearly NOT a hardware problem. I REFUSE to throw away and replace a dozen adapters just because Dell decided not to allow them anymore. That is NOT their decision to make!

 

It sounds like this type of throttling is being controlled by the BD PROCHOT function. Use ThrottleStop and make sure that is not checked.

Download ThrottleStop 7 from my signature and post some screenshots of how you have it setup. Maximize the Set Multiplier value, make sure that option is checked and then click on the Turn On button. I am just curious. Most of these problems can be solved.

 

I'll give it a shot, since you asked nicely and seem to want to help. I'll point out the 5+ minute bootup, and my default OS being Linux as for why this is not a solution for me.

Will add results here shortly.

Throttlestop under A06: http://i.imgur.com/6l4MBdw.png
Throttlestop under A11: http://i.imgur.com/91QPkuB.png (180W AC)
Throttlestop under A11: http://i.imgur.com/g8TazBD.png (90W Battery)
Throttlestop under A11: http://i.imgur.com/lriZ1wa.png (120W AC)

Unchecking bidirectional ProcHot didn't do anything (edited for poor wording. Tried a lot of different combinations of things.)

 

What is "throttlestop"?

 

Hi everyone.

I've owned a precision m4800 laptop ( i7 4800mq @2.7ghz 8gb ram with win 8.1 pro) . However, it seems like the task manager and other software like speccy and Cpu-z show that my laptop only have 2 cores and 4 threads instead of quad-core and 8 threads. So anyone can explain it to me, please?
If this is a issue, can you show me to solve this?

Beside, i've updated it's BIOS to A11 by dell support web.

 

What is "throttlestop"? [...] OK that question has already been answered....

unclewebb is the author of Throttlestop. So maybe -if he is willing and if the tool works under Windows to fix our problem-
the tool can be ported to Linux or maybe the relevant parts condensed into a Linux kernel driver.

 

does anyone know the part number for the qhd screen, would it be user replaceable, is it only glossy touchscreen or is there a matte version. I only ask because I can get a good deal through my work for the m4800 or m3800 but it's the lower resolution model.

 

I believe it's a different motherboard.


Sent from my iPhone using Tapatalk

 

Can you go back and have a look at the screenshots you posted? In 3 of the 4 screenshots, ThrottleStop is in Monitoring mode which means you have ThrottleStop setup so it is not doing anything to help with this problem.

Finally in your 4th screenshot you click on the Turn On button but all of your screenshots show that you did not check the Set Multiplier box. This needs to be checked so ThrottleStop can try and adjust your CPU speed. If you can run your tests again with ThrottleStop properly setup, it might be able to help. If you are still having problems and are stuck at the 8 multiplier, post screenshots of the TPL and TRL windows.

On your second screenshot it shows power consumption at 48.5 watts. The Core i7-4800MQ has a power rating of 47 watts. The way Intel designed these CPUs is that long term, the CPU will throttle and run slower to keep under this power limit. This throttling that takes place has nothing to do with the power adapter you are using. It is a feature of the CPU. The other thing I noticed is that PROCHOT 97 is checked. That means the CPU reached the thermal throttling temperature while testing. PROCHOT stands for processor hot and Intel sets that to 100°C for the 4800MQ. They also provided a way for individual laptop manufacturers to lower the thermal throttling temperature by using an offset feature. It looks like Dell is using a -3°C offset so your laptop will start to thermal throttle and slow down when it hits 97°C instead of the Intel rated 100°C.

There are usually only a couple of registers in the CPU that control the speed the CPU runs at. ThrottleStop bypasses Windows and writes information directly to the CPU. If we can figure out exactly what method of throttling that Dell is using, it should be easy enough for someone to create a similar fix when using Linux.

Anh Tu - You have half of your CPU disabled. This can almost always be fixed by running msconfig. Click on the Boot tab, then click on the Advanced Options... button and make sure that the Number of processors box is NOT checked. After you do this, click on OK and exit msconfig. You will need to reboot after you exit msconfig. After you reboot, Windows will be able to find your missing cores.

http://i.imgur.com/Y9z2oB7.png