Slow Performance without proper Power Adapter after BIOS A8 update on M4800?

I'd like an explanation from Dell as well.

If I'm correct, the crippling started with A07. I have the i7-4900MQ CPU with "Max Qualified Speed" at 2.80 GHz (multiplier 28) and "Max Turbo Boost" speed at 3.79 GHz (x38 ratio). Independent of the BIOS version (A06, 07, 08 or 09), when on the 180W AC power adapter, the CPU runs at x36 ratio i.e 3.59GHz. Even without any processing load. The same goes for battery power, whatever the BIOS version, the CPU speed is at x 34 ratio i.e 3.39 GHz. Again, without any load. On battery power the CPU is at a higher speed than the "Max Qualified Speed" without any need for the Turbo Boost.

Now the problem arose with the version A07 and exists in all of the following versions. When you plug in an adapter which is less than 180W, I have several of the 130W ones, the CPU multiplier drops to 8 which is the absolute minimum and makes up 800MHz. Ridiculous! Right after you remove the power supply you get an immense 3.39 GHz, over 4 times the speed when on AC.

As I need to use the laptop on a dock which has the 130W power supply weekly, I've reverted to BIOS A06 first. The computer is unusable at 800 MHz, it's like going 15 years back in time. The most noticable feature of the newer BIOSes that I like is that they somehow optimize the fans and make them quieter.

Does anyone if there is a limit on how many times the BIOS chip can be flashed?

I'd like Dell to explain why they have made such a move. And eventually fix this with A10!

I can confirm this from my organization as well. On our E6440's if users use the following:

• Universal Power Supplies (that meet the power requirements)
• Dell 60W Power Supplies

It'll basically cripple the laptop causing device problems, sound problems, video problems, performance problems.

Unplugging the power supply resolves the issue immediately in all cases.

Anyone know what changed in BIOS A8 and what the deal is with the performance?

I would like to know this too.

I have a workaround for the problem, but it is a workaround and not a fix.

Go into the BIOS (F2 during boot), go to the performance tab, and disable "Intel Speed Step" technology.

I won't go into detail about what speed step does, google will do a better job at that. The effects you should notice are:

1) Increased performance, on docked, plugged, and battery

2) decreased battery life due to increased performance.

This thread helped me figure out this problem.  The workaround provided by gazofnaz seems to have worked for me.

There was one difference that I wanted to document for anyone who comes searching.  I have bios version A14.  I have also been having slow performance when I am unplugged, as well as when I am on a <180W adapter.  I wonder if they decided to "help their users save battery life" by this idiotic performance cut when not plugged in at all.

Has anyone else experienced that?  Previously it seems you could unplug your 120W adapter (for example) and performance would go back up.  I almost always work plugged in, so I'm not sure when my issue started occurring.  

I worked with an M4600 at a customer and were up to equip my company with these machines.

But then I had to carry the extremely heavy original power supply (230W or so) - absolutely not suited for a mobile computer!

As I connected a smaller power supply from Dell, I also experienced this problem of extreme

loss of performance.

I measured the power consumption: it is at about 32 W - the small Dell power supply (well suited for traveling) delivers up to 130 W! Obviously there is no technical reason for this strong throtteling.

This customer treatment is preventing me from equipping my company with Dell.

There is an excellent solution to this problem: use ThrottleStop.exe and set multiplier to 20 and Power Save. Everything runs as you would like savely.....