[snippage]
Thanks Paul. I removed one stick of Samsung 4GB DDR2 RAM and there is
progress. The BIOS never stops, it keeps trying repeatedly. I'm still
trying the get a better handle of front panel wiring. Beep codes would
give more debug info. Now the spinning of the CPU fan is concurrent with
GTX 970 fan. But still no output on HDMI. I may be able to get an early
2000's ATI Radeon VGA card locally for $5. The BIOS screen might be seen
without solving beep diagnostics. Maybe not. So I'll need to get BIOS to
recognize GTX 970. It worked on my old build.

It is said that when confused sleep. This confusion makes me very sleepy.
After sleep I arrived at some working hypothesis:

1. The front panel connectors are meant to be dynamic not static, so I moved
split POWER LEDs to SPEAKER+ and Minus.

2. If one RAM stick is good zero is better.

Observations: Still no beeps. Fancy color RAM LEDs still glowing. Continuing
CPU reboot cycle. Still no HDMI BIOS page from PCIe GTX970.

Working conclusions:

1. Zero or one RAM sticks makes no difference. Might as well use one.

2. Don't know function of RAM LEDs.

3. I still don't know operation of SPEAKER+ and SPEAKER-. No beeps. Does it
matter? Every time I use recommended polarity, I fail.

4. A PCI VGA adapter would be nice.

5. PCIe GTX970 will never be recognized until I boot Wn10 OS.

6. I will reinstall one RAM stick and wait for further sleep.