I have misplaced the original charger that came with the VP8. I always use my Amazon Kindle charger for my cell phone and also for my VP8 since I bought it last October.
Well, I purchased a Plugable Pro 8 Charging and Docking station. I unboxed it, plugged in the wall outlet, and plugged the VP8 to the microUSB plug with the other end of the cord into the USB socket.
No charging light! ARGH! So I plugged the VP8 into the Amazon Kindle charger plugged into the wall. Charging light comes on!
Then, I take the Amazon Kindle charger out of the wall, remove the USBtoAC plug and plug the USB end into the Plugable Pro8 Charging and Docking station. NO CHARGING LIGHT. ARGH.
So I take the Amazon cable and plug it into a USB socket on my Lenovo laptop. NO CHARGING LIGHT. I try three other USB cables with microUSB to the VP8 and the other end plugged into the USB socket of my Lenovo laptop. NO CHARGING LIGHT.
What the...? Does the VP8 not charge from a 5V USB source? That is going to render my Plugable Pro8 as worthless.
A typical USB laptop port provides limited power--only around a quarter of the amperage that the DV8P wants. And so the charging via your laptop may be occurring (slowly) but the charging light not lighting--or there just may not be enough power to start the charging process.
As to Plugable, I would contact them, as they seem to aim to please, and my understanding is that the device indeed should work as you attempted.
The Venue 8 Pro needs a 10 watt charger. At 5 volts that comes to 2 amps, so look for a charger rated at 2.1 amps. A USB port on your computer isn't going to cut it.
Working well: the Blackberry Playbook charger available thru Amazon.com, at a very reasonable price; 1.8 Amps but still just fine. With a 6' attached cable and foldaway blades.