XPS 27 (7760) - Laggy when using software...

Hi guys,

I've just really got my XPS27 setup - I'm planning on using it to replace my aging Vostro 360. I do a lot of Adobe Animate / Photoshop work.

The problem is my XPS27 -- is just SO laggy when trying to work - moving objects around the screen, like movieclips, or parts of a photo. You click an item - hold down the mouse key, and instead of moving, you don't see the result until you let go of the button - then the item "jumps" to the location. So it makes fine detail work impossible.

The same for text - you click text, and drag your mouse to resize text - and there is no live updates - once you let go of the mouse button the text appears the new size. It's horrible to use - especially when its running fine on my Vostro360. The only reason I upgrade was for the nice new 27inch 4k screen.

I've used photoshop and animate (flash) for YEARS and I am sure it's not settings in the software causing the problem. I have it all set to use max settings.

I feel like the xps27 isn't using the graphics card - and is trying to only use the on-board graphics. Trying to change this using the Radeon crimson software is near impossible. I've set both software to "maximum performance" in crimson - but it makes no difference.

I've tried to find if hardware acceleration is enabled - but I cannot find that anywhere.

I've also changed different bios options - but again, no luck improving the lag.

I'm starting to wonder if the graphics cards aren't up to the job of editing on a large 4k screen - it is a laptop graphics card after all? (Is anyone having luck with theirs?)

Any advice or ideas would be great! I've also emailed support.

The last thing - my invoice says the machine I purchased should have a AMD R9 M485X 4GB GDDR5 - but my system has a AMD R9 M390X -- is this the same card (relabelled?) or has Dell downgraded my graphics card?

Thanks again for any help!