Check the BIOS setup - if the system isn't identifying the AC adapter, it won't run at full power.

If that's the case, replace the adapter first - if that doesn't solve it, the problem is with the DC jack or the mainboard.

(this is my adaptor)

Thanks for the quick response,

When i get into BIOS it seems quite limited on what i can do lol, how would i check the adaptor?

Sorry if im being an idiot.

thanks

joe

On the main screen you should see the adapter identified.  If it shows unknown, there's a problem.

Based on the appearance of that plug, replace the adapter ASAP.  If it short circuits the mainboard, a simple $50 or less adapter replacement will turn into a several hundred dollar mainboard replacement.

Had a look in the BIOS, heres what i found.

AC Adaptor Type [240w] 

Intergrated Graphics [Not Detected]

Discrete Graphics [Nvidia GFX]

There was obviously a lot more jsut htese were the relevant ones

Still think its definitely the adaptor?

Just thought, is there a way to change the laptop to use the Nvidia card no matter what, surely that would test to see if the adaptor is the problem.

Makes sense!

nothing but problems with this laptop. lifespan of 2 years is very dissapointing.

already had dell coe out and replace parts about 5 times while it was in warranty.

thanks for the advice, when im able to grab one ill post back with results.

It depends on whether the adapter is staying connected - from the appearance of the plug, it's very possible the adapter is losing contact with the mainboard intermittently, which will indeed cause the system to throttle back.

I would replace the adapter first, before going further with troubleshooting.  If a new adapter with a good plug doesn't solve the problem, it may be you're seeing a video card that''s on its way out.