What to do? Buy a new motherboard and rebuild? Or wait for failure?

I’ve got computer problems. Don’t know what to do. I’ve a Windows PC, custom built, about 5 years old with an Intel Core i7 mother board. I’ve recently added Windows 10, so now It’s a dual boot Windows 7/Windows 10 with an SSD for the Windows 10 OS and and a HHD for the Windows 7 OS, a 4 tb RAID array for holding my data, including music. It has an internal sound card, the ASUS Xonar Essence II. Recently had to replace the power supply. All primo components when new.

Externally, for sound I have an Audiomat Arpege Tube amp and Spendor S3/5 Monitor Type speakers. I have a Roon subscription, and a Rega CD player and I can get some pretty nice music to listen to. That is IF the sound card works. It usually doesn’t.  

So the computer problem is vague. Computer crashes on me, and I will have to reboot. Or it just freezes sometimes. Nothing very significant, but I just have an instinctive feeling something is wrong. My tech tells me there’s no easy way to diagnose “instinct”. Which I definitely understand. He advised me to keep it until it actually fails.

BUT, there’s another issue. I hate Windows 10 and want to stick with Windows 7 (which is why I have a dual boot system). So If it takes a long time to fail, maybe I won’t be able to buy a motherboard that supports Windows 7. How much longer will motherboards that support Windows 7 still be on the market? (I’m not even sure I can still buy one.) So I keep thinking I need to buy a new motherboard NOW, one that will support Windows 7 while they are still available. I will want to build a reasonably quiet computer, one that minimizes at least some of the criticisms about computers for audio. But, much as I’d like to I cant afford to go overboard about sound.

So finally I get to the important bits.

Is there a favored Windows 7 motherboard for audiophile computers?
Do I really need a specialized power supply, or can I reuse my almost brand new one?
Do I need all my hard drives to be SSDs? Or can I reuse all my existing hard drives?
Do I need a specialized video card? (I don’t play video games.)
Is there anything I’m forgetting to ask about?

Another topic, but I’ll mention that I have a lot of problems with my present internal sound card. The dang ASUS Xonar Essence II sound card won’t stay up and running. I’ve twice sent it to ASUS, who tell me nothing is wrong. I’ve three times hired a tech to see what’s wrong and they eventually get sound out of it, but it just won’t stay up. It’s down again today. Zero sound. I’m ready to throw the ASUS card in the trash at this point. I’ll want to invest in something external to replace it. So my ASUS sound card is not a candidate for transfer. I’ll need to buy an external  DAC and I don’t know what else. But first priority is a new custom built computer.