I ran attract-console.exe and it says that hardware acceleration is not available (see below for full output). I believe this is correct, since this is an older laptop I don't think the video card supports hardware 3d. I have the latest Windows Update video drivers installed, I don't think there are any newer Win10 drivers since HP doesn't support Win10 on this laptop.
According to task manager there is still enough RAM available and the CPU is only going to 40% when using the menus.
DirectX: According to a Microsoft page I found, it said DirectX is included in Win10 so there isn't an installer?
I did some further testing:
If I remove all of the displays and go to the config menu then it is fast. Up/down keypresses are responsive.
If I add one display with one MAME rom then things slow down again. The number of ROMs that I have doesn't seem to affect the speed.
I tried a few different layouts and all of them were slow.
Maybe the software rendering is just slow when there is a layout that needs to be displayed?
attractmode-console output:
Attract-Mode v2.6.1 (Windows, SFML 2.5.1 +SWF +7z +Curl)
avcodec 58.54.100 / avformat 58.29.100 / swscale 5.5.100 / avutil 56.31.100 / swresample 3.5.100
Config: C:\arcade\apps\attract.251\attract.cfg
- Constructed 1 filters in 0 ms (1 comparisons)
Warning: Detected "Microsoft Corporation GDI Generic" OpenGL implementation
The current OpenGL implementation is not hardware-accelerated
Setting vertical sync not supported
OpenGL extension SGIS_texture_edge_clamp unavailable
Artifacts may occur along texture edges
Ensure that hardware acceleration is enabled if available