Lets hope that Digerati drops by and takes a look at your post, as what he doesn't know about Power Supplies and the calculation tools is not worth knowing!
Geesh, nothing like a little pressure here!!! lol
1. What program can help me find out what my current power supply is?
There isn't any program that will tell you what your current PSU is. PSUs do not provide that type data to sensors. To determine what you currently have, you will have to remove the case side panel and read the label (99% are visible without having to remove the PSU). While in there, as I mentioned in your other thread, make sure the system is clean of dust and the fans all turn freely. Sadly, you cannot even determine the PSU reliably from the PC maker's website as they often supply something other than what is listed on the specifications page (fortunately, a bigger supply is normally thrown in).
All a software program can do is verify the voltages are correct, and, depending on the PSU model, the rotation speed of the PSU's fan. Since the required voltages have been established by the "ATX Form Factor" industry standard, you don't have to worry if a PSU delivers the correct voltages (other than to ensure the PSU is not malfunctioning). The ATX Form Factor standard requires all ATX PSUs to be of a specific physical size and shape so that it will fit in all ATX Form Factor cases, and that it will have a minimum number and type of connectors so that it will properly connect to and properly power ATX compliant motherboards and peripherals. So, the problem for new PC PSU buyers is ensuring there is enough total wattage, and, increasingly more important, enough current on the +12V rail. Think of "rail" as the electrical circuit for that particular voltage, with the understanding that a single rail may supply voltage to more than one connector.
You are wise to be concerned about the power requirements for your graphics card. It is graphics cards that is driving the current on the +12V rail issue. This is because graphics cards are now the most power hungry component in the computer - surpassing even the CPU.
2. Is there a program that can help me work out how much power I'll need for certain graphics card, etc.?
Use the
eXtreme PSU Calculator Lite to determine your power supply unit (PSU) requirements. Plug in all the hardware you think you might have in 2 or 3 years (extra drives, bigger or 2nd video card, more RAM, etc.). Be sure to read and heed the notes at the bottom. I recommend you set Capacitor Aging to 30%, and if you participate in distributive computing projects (e.g. BOINC or Folding@Home), I recommend setting TDP to 100%. Research your video card and pay particular attention to the power supply requirements listed on your video card maker's website for your card. Then look for power supply brands listed under the "Good" column of
PC Mechanic's PSU Reference List. Ensure the supplied amperage on the +12V rails of your chosen PSU meets the requirements of your video card. Don't try to save a few dollars by getting a cheap supply. Digital electronics, including CPUs, RAM, and today's advanced graphics cards, need clean, stable power. A good, well chosen supply will provide years of service and upgrade wiggle room. I strongly recommend you pick a supply with an efficiency rating equal to, or greater than 80%.
If you are not certain what values to plug into the calculator, post back and we can help you. For sure, you will need to to determine first which CPU you have and the type and number of RAM modules, and the number of hard and optical drives. If you do not know, Belarc Advisor and Everest from your other post can help with that too.
Determining the PSU requirements is not an exact science. Round up if unsure. It is a waste (in money) to buy too big of a supply, but, if a computer needs 400 watts, then all else being equal, it will draw 400 watts from the wall outlet, regardless if the PSU is a 500W supply or a 1000W supply. So it is not wasting energy, nor will it harm the computer in any way if you buy a bigger supply than you need. It just means you have a little more wiggle room for future upgrades and added hardware.
