Could anyone please tell me the attributes I should be looking for in a suitable MoBo for my system ? Many thanks in advance
This is such a wide-ranging subject it’s hard to know where to begin, but there’s the Steinberg recommendations for DAW components, for example. While it doesn’t go into specifics on mainboards, it does mention chipsets in general terms without mentioning any particular menufacturer.
The problem with asking about this on internet forums is that everyone has their own preference, and indeed everyone will argue that their own personal choice is best, perhaps as part of a subconscious effort to justify the financial outlay, or denial following a spectacularly bad purchase, and need to talk the item up.
Nevertheless there are a few patterns that have emerged over the years so I’ll start the fun by suggesting that currently, Intel appears to be the preferred CPU/chipset, with both Asus and Gigabyte as popular mainboard manufacturers; the X99 chipset is stable and widespread, and the Z170 is close to cutting-edge, but has its quirks.
Personally I have found it beneficial to use a mainboard with at least one (old) PCI slot for backward compatibility with older external devices, but you may not have any, in which case avoid them. Avoid “gamer” video cards as the drivers do not care about audio and may cause glitches; the built-in graphics capabilities of Intel i5/i7 CPUs are more than enough for a DAW. If you really must have a dedicated GPU for other applications, currently AMD cards (formerly ATI) seem to cause less problems for realtime audio than Nvidia.
If you intend to use the same machine for both gaming and audio processing, as a personal request please state that in your sig, so I can ignore your posts. I have nothing against gamers, au contraire, some of the best information on how to push current technology to it’s limits can be had on gaming websites. When it comes to gaming and DAW use, however, just as with the grape and the grain, I believe it’s best not to mix them.
If you’re considering a new self-build, one simple suggestion is to have a look at websites of reputable DAW-specific builders, and you’ll be able to figure out what components they use. You might not, however, be able to figure out how all these components can be made to work flawlessly together for realtime audio processing; that’s why, unless you are really, really into the idea of building a DAW yourself, have some experience in putting PCs together and the time, patience and endurance to solve all potential incompatibilities, are prepared for a very long learning curve and finally, possess a penchant for masochism, you might want to consider just going for a pre-built system from a reputable DAW builder.
Above all, have fun, but beware – I started as a musician and ended up working in IT. 
The above is sound advice.
I personally try to get a motherboard as basic as possible. Any additional features I’m not using anyway can only cause trouble.