Laggy blender in render mode

I just started creating a project in blender, and I noticed that it starts significantly lagging as soon as I use the render mode. It lags slightly for 8 faces cube and lags horribly for 28,000 face object.
I believe that this is something wrong with blender, as my computer is pretty good and can play most modern games at highest settings with ease. Here’s my config:

i7 4700MQ
Nvidia GTX 740M

What am I doing wrong?

Hey. I assume render mode is the mode where you switch render like view while modelling. If so, take a look at render preview settings. Maybe you have too great number of samples or full illumination. Other thing, if you render using gpu which is used by your system and that’s the only gpu you have, your gpu simply is taken away from rendering view and windows etc, and is used mainly for render preview. Therefore, rest of the system could be less responsive. I hope that my reply makes sense… :wink:

Sent from my iPhone using Tapatalk

My processor has intel HD 4600 on it and along with that I have a GTX 740M. I can play games such as Crysis, Assassins creed, Gears of War etc. on max quality with ease. I don’t know why blender starts to lag

Gaming performance is a totally different pair of shoes. When you play a game, the sole job of the graphics card is to display the game content - and it may do that admirably. But rendering on the GPU means that you throw all available resources of your card at rendering the image, while having it do something completely different simultaneously: Displaying Blender and running the OS’s user interface. That’s not going to work without the latter suffering heavily…

In addition to that you’re using a notebook-class graphics card (GTX 740 “M”), which is nowhere near as powerful as its desktop counterparts. In fact, I doubt that this card will show a significant performance gain over rendering on the CPU.

Your GPU is too weak.

For rendering,you want one of these:

They go for around 2k dollars.
It’s useless for gaming though.

How do I replace my 740m with a k5000?

Since it’s a laptop,you won’t be able to.