Eatmc7

I see no reason to uninstall the IGPU driver

Please don't. If someone else has the same issue and finds your thread in a Google search, they'll be happy to have a few pointers.
 
I've reinstated the thread.

It should work as long as they run at the same speeds/timings, but I wouldn't recommend it. You would be better to just get a new kit with 2x 2gb sticks. Also I found this on the website: 
 

Just imagine you have the responsibility to setup a new vault for the queen of England's crown jewels. 
Would you put those precious items behind a high end security system that is powered by a single AA Battery? And risk somebody would just take the battery out and steal the jewels? 
 
Now instead of jewels you have PC hardware, instead of the AA battery there is your crappy PSU and instead of stealing, I mean blow up and kill everything. 

The operating system is copying stuff to the stick until its internal DRAM is full, then the stick stops to write the stuff from DRAM to the flash and then again accepts more from the OS. The controllers on USB-sticks are pretty cheap and simple compared to e.g. SSDs' internal controllers and this kind of behaviour is quite normal for them.

The Haswrll GPU is larger and thus separate. A normal desktop CPU looks the same