dany_boy

Hey thanks for sharing your experience. Like you said, losing some performance will be almost inevitable to significantly lower power draw. Still, having confirmation that its doable is pretty much all I needed to know

Hey everyone, I'm curious if anyone has personal anecdotal data on undervolting amd cards, more particularly the 6800 xt. I'm looking to upgrade my 2070 super to a 6800 xt. While my power supply should be more than fine (corsair sf750 platinum), I'm a little concerned for cooling performance. So if anyone has hard evidence that the rx6800xt can dissipate say 250~ish watts while maintaining a decent level of performance I would really appreciate any advice. Or just any AMD undervolting data in general, in terms of power dissipated vs lost performance. I'm well aware that I'll probably be sacrificing some performance, I'm more interested in running cooler overall. Cheers

Hot damn! salt much? I feel like we both need to calm down and watch this video instead of turning the forums into youtube comment section: That being said, I still stand by the point I said, specially given the lack of concrete evidence that you have provided. Either way, on Monday I'll borrow some equipment from my Uni labs and perform measurements with a remote sense feature to eliminate the small resistance in the wires. I will use a clamp meter too if I can and we can them compare concrete results. Cheers!

Ok Im back (the seafood was absolutely awesome BTW). HAHAHA it really cracked me up. Almost reminds me of the YouTube comment section. For your peace of mind, here are my meters: And here is why I say that that the shunt resistor in the mA range of a meter is only a couple of ohms: I have been doing electronics for the last 7 years of my life, 2 of my uncles (who have masters degrees in electrical telecommunications engineering), as well as my professor of electric circuits (with a PH.D in some digital electronics design subject) have taught me that the resistance in a good meter while measuring current, is not significant to the current measurement value for any given range. If you have another explanation, or you feel like I have been lied to, please explain yourself with actual theory, data, and calculations. I am more than happy to listen and change my mind. But the way I see it, a component with an ESR of 83 ohms is not gonna be hugely affected by 3 ohms more in a very significant way. @5chmidti Here are some measurements that I took with a 30cm length of wire between the ardiuno and the LED strip: 1 LED all white: 3.945v -- 16.35mA 2 LEDs all white: 3.832v -- 31.31mA 5 LEDs all white: 3.702v -- 72mA (had to change the scale) This is of course a non-ideal scenario, since I'm feeding the arduino + LEDs with a PC USB 1m long cable. But it should give you a rough idea of what to expect. Next week I might have time to collect some more controlled data. Let me know if you want me to do this full on "lab report" along with uncertainties and all that cool stuff. Cheers!

<sarcasm> sure I'm just pulling all of this out of my ass to troll people </sarcasm> Ill be back in a couple of hours, then we'll keen on discussing.

I just went out to eat, if you give me a couple of hours I can provide you with a detailed explanation and calculations. In a nutshell, at full brightness a single well fed led will consume a little under 60 mA. (Big emphasis on single and well fed) Cheers!

Dude, come on man. Ok Here we go. First of all I apologize if I come across as pedantic or condescending, it is really not my intention. That being said, please inform yourself before giving ill advice on how to use electronic equipment. Take a look at the uni-t product specification for the clamp mete, particularly at the current capabilities: DC Current (A) 2A/20A/100A ±（2%+3) and consider this is a 2000 count meter. that means that if you are gonna measure a current in the order of (3*10^-2) A, your precision is gonna be ±2% (not a big issue), and ±3 counts which considering the order of magnitude of your measurement will equate to about 10% of additional relative error, which is huge! Plus the fact that even after zeroed out, clamp meters tend to drift. This one in particular has been found to drift in the 2A range up to 40 counts after 1 minute with crappy batteries and 10 counts in a minute with decent batteries (source). Again, for big currents, that is really not a big issue, but for the case here it is. Now take a cheap-o multi-meter without a μA range. This is important because the μA range has a rather large 400-ish ohm shunt in series. The mA range on the other hand, will have a shunt of a couple of ohms for most meters. Looking back at the error, most crappy meters will have 2000 counts too, with a precision of 2% ± 5 counts (based on experience with them). At a current in the order of (3*10^-2) A, you will get ± 2% (again not a big deal), but now with the 200mA range those 5 counts will only equate to about 1% of added relative error. So for small currents, a crappy meter is somewhat better than a clamp meter. And if @5chmidti does not have a clamp meter already, then that is money he could have spent buying a good multi-meter in the first place. Cheers!

Keep using the meter that you have, clamp meters are only good for fairly high currents otherwise the precision will screw you over big time.

Are you for real? Or just trolling?

Not as portable though. The really amazing thing about the spark is all the technology they managed to put into such a tiny form factor while still maintaining a 10+ minutes flight time.

DJi dominating the drone enthusiast market? HAHAHAHA yeah right. Still a great vid though

If the amp works with 5v and draws less than 1A, then it should be perfectly fine.

Use HDMI. VGA is garbage in this day and age, stay away from it. Some "DVI-d" cables are actually fake, try to stay away from the cheap and thin ones.

Just provide the strip with 12v and enjoy the lights. The strip has integrated current limiting resistors. Cheers!

What I'm trying to say is that connecting the solar array directly to the battery without any form of proper charging circuitry will significantly reduce the lifespan of the battery. Most Lead-Acid batteries don't even like being charged at more than 0.5C, and given the capacity of the battery (what I estimated) the solar array will charge it way too fast, not to mention the lack of proper monitoring. Sure it can be done, but its janky AF.

@cj09beira 10 virtual cookies say you are wrong: Data taken from here: http://www.bestbuy.com/site/cyberpower-450va-battery-back-up-system-black/3938808.p?skuId=3938808 Best case scenario: 7 minutes at half load. Load = 260W of real power. 450W of apparent power. 130W * (7/60)h = 15.67J of energy provided. Assuming converter is very efficient (85 ish percent): (15.67/0.85)J = 18 ish joules. Average lead acid battery voltage: 12v --> (18 Wh /12v) = 1.5Ah of battery capacity Also, charging phases: http://batteryuniversity.com/learn/article/charging_the_lead_acid_battery

Can't see anything, RIP dark theme users. Please use auto formatting and use the code functionality next time. Gimme a sec while I make this readable for myself

Do you want to reduce the lifespan of your batteries? because that is how you reduce the lifespan of your batteries

The actual code would be helpful you know

Erm, over-voltage, over-current, over-temperature protection? Charging phases?

Get an inverter, preferably one with a modified sine wave topology.

Hahaha Basically, dont use a commercial UPS that charges from a solar inverter, its too inefficient. It's way better to use a (MPPT) Maximum Power Point Tracking circuit to directly charge a battery from the solar array. After that, you may use an inverter to power whatever you may need with mains voltage.

@XCalisseMunematzX Again, don't bother with an inverter + UPS, the efficiency takes a nose dive. Get an MPPT directly to a battery. If after that you want to power a load, then you use an inverter.

You might as well by-pass the inverter and computer PSU completely. It is doable, but it will require full on sunlight. I would try to use buck/boost converters to get the necessary rails for a PC to operate. If you really want to do it, we can discuss further, but I don't think it is a particularly good idea. Cheers!

It's to provide extra power for the USB ports