Question 1

Does anyone know what the Diameter of the base is?

Accepted Answer

I don't have mine anymore, but it's about 2 and a half inches or so. If you were to set it in your hand it covers about as much spaces as typical AIO coolers cover a Threadripper if that makes any sense at all.

Question 2

Would this work with an older Lenovo desktop?

Accepted Answer

The mother board should have the pins for the case switches power reset and the leds for power and hard drive. Follow the case wires to the mother board. They should be marked on the mb the dyi unit is marked. Solved my aging case buttons on my antec nine hundred which is ten years old and has had several sets of hardware. Thanks to this unit it is still kicking.

Question 3

Hello, regarding the "Corn replacement DIY Desktop Power Button Module Switch for PC Computers", why do some of these retrofit buttons have like 8 leads, while others have 4, with as little as 3 actual connectors? Shouldn't the number of connections be the same for every computer?  Unclear as to which one I should buy for a Lenovo K330B series without taking it apart first.

Accepted Answer

did you buy it already?  I am looking at mine on my desk.  it has one sept 1pin lead for power led AND one sept 1pin lead for power led - AND one 2pin lead for hdisk led AND one 2pin lead for reset switch AND one 2pin lead for power switch.  For switches you just have to press the power or reset button which creates a closed circuit, so it does not make any difference which pin the plus lead or the minus lead goes to.  For the hard disk led and the power led, they will not cause a problem (damage) but they will not light up the leds unless the lead labeled + is connected to the pin labeled plus etc.  The power switch, reset switch and hard disk led leads all consist of two leads next to one another for pins next to one another on the motherboard.
This should be standard.  The power led on most motherboards is usually as described later, ("standard") and in addition there may be an optional power led connection on the motherboard (you can pick either one standard or optional they both work).  Here is the standard layout FOR MOST MOTHERBOARDS as far as I can tell:  two rows of five pins.  
Bottom row left to right pins 1,3,5,7,9;
top row left to right pins 2,4,6,8,STUB.  You can not physically connect anything to the STUB.
pin 2 is above pin 1, pin 4 is above pin 3, pin 6 is above pin 5, pin 8 is above pin 7.
top row
(pin2 = +pwrled)(pin4 = -pwrled)(pin6 = pwr switch)(pin 7 = pwr switch)(STUB)
bottom row
(pin1 = +hdled)(pin3 = -hdled)(pin 5=reset)(pin 7=reset)(pin 9 = open or sometimes ground)
as you can see the pins for hdled are adjacent and the leads are adjacent too (they fit !!!)
the same goes for (a) the reset leads (b) the on/off switch leads. 
Usually as in this case the power led pins are adjacent and there is a separate "optional" set
of power led pins in case your leads do not fit the first pins.  For the Corn product you want to buy the power led leads are separate so you can fit ANY pins.  They are all beautifully LABELED!!! look on pins and motherboard.

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