Help me to choose a power supply please

Hi Guys, I was hoping to get a new PC this year but times are hard and so I will have to stick with my current setup for now I think my current PSU is on it's way out and was hoping to get a new one. This is my second PSU and it is a cheap brand called Cit,it is a 650 watt. I would like to get a decent brand quality one this time but don't want to spend loads on a psu that is way above my requirements e.g buy a 750 watt when all i really needed was a 500watt. I have tried a couple of online calculators but can't figure out my requirements and I would like to check with someone incase I bought say a 500w when I really need a 550w to run my system. My current setup is : Asus p5n-mx mobo with nvidia geforce 7050 chipset and 4gb ddr 2 ram. Intel e8500 core 2 duo processor and stock fan(not overclocked). Sapphire AMD Radeon HD 6450 1GB GDDR3 graphics card connected to LG 22" lcd monitor. 1 x Sata Hitachi 320gb Hdd 2 x DVD rw Combo drives 6 x built in usb slots with the following connected to 4 of them while 2 are empty 1 x Card Reader (runs from usb port) 1 x 4 port usb hub(unsure if running from mobo or an internal usb port) 1 x usb mouse and keyboard 1 x Line6 Toneport GX 1 x Epson sx415 printer/scanner Galaxy PC case with 2 tube lights 1 x 120mm rear fan 3 x 80mm fans(one has led) I can't think of anything else. I won't be expanding my set-up in future as I will be saving for a new setup. If anyone can calculate my required PSU and give me some recommendations that would be great. thanks!

Skimping on a PSU is crazy, it is the heart of your system, and if it goes bad it can take your entire system with it in the worst case, I would personally suggest getting around a 750w unit, it's better to have more power than you need, it means it doesn't need to work as hard to do the same job, and will last longer as a result, if you have a price in mind, we may be able to suggest something more specific, but I would look to Corsair personally, very good units as a rule, and if you intend upgrading further down the line you need to be sure what you get now can handle what you get later, hope this helps a bit anyway.

I was only hoping to spend £40 was looking at this one OCZ StealthXstream II 500W PC Power Supply The reason I was looking not to spend alot was because I was going to give my existing PC to a relative later on when I complete my new build as I want to start my new build with brand new gear. If I buy a quality PSU just now I would then be switching it to my new build but will have no psu for my existing unit and don't want to put another cheapo in the existing PC.

I understand what you want to achieve, but I fear you will be cutting your own throat doing this, to start with I personally would not use that unit, my main reason is a report I saw said this one is actually manufactured by FSP, and I had a bad time with an FSP unit (took out my motherboard), but there are other points to bear in mind as well, for starters the available connections are very limited, and would almost certainly not be enough in most new builds these days, not unless you will be using minimal components, eg this only has 3 Sata leads, and dependant on what video card you get it may not have the connection for that (it only has a 6 pin, some have an 8 pin), you may end up wanting 2 video cards needing twice the connections\power, and most state a minimum power requirement. Another major point to note is the numbers on the box, to get a "750w" supply does NOT automatically mean it is better than other lesser units, you MUST take note of the amperage supplied down the cables, a 500w unit could be pushing a higher amperage down it's rails (this is how they describe the power leads), it goes far deeper than I could explain, or even understand fully, but I know the points to watch out for and have laid them out here, long story short if you want this to power a high end system you will build later, then you need to look at what sort of power requirements it will need, and buy appropriately to that, not for this current system, but you could ask the person you will give it to if they would pay for a PSU for this system, your price for that above is very doable. I suggest spec’ing the system you intend to go for, not the physical make\model(s) as such, but figure out how many Sata leads you will need, eg how many drives you will use etc, see what sort of power and connections a video card will need, then look at PSU's that have the required connections that you require, and if it had a few extra left over it may be handy for future changes. Then take notice of the amperage on the rail(s), some makers split the load over 2 rails (maybe more for all I know), others use a single 12v rail, many prefer a single rail, myself included, others prefer multiple rails, the main point to note with multiple rails is what you connect to each rail, you "could" overload a rail by putting numerous high demand components on it, a single rail does not have this issue as it spreads it ALL out evenly, although you still have to ensure not overloading it (very hard\near impossible with a good single rail unit), you don't need to worry about what lead you connect what to. The unit you mention above is not a good one as I said, BUT, OCZ have bought out PCP&C (PC Power & Cooling) which are the Rolls Royce of PSU's, so they certainly have good units, you just need to research them before buying (true no matter which one you get), for the average person (myself included) this can be quite perplexing, so I tend to look for other reviews of a unit I shortlist and see how they rate it, Toms Hardware is such a place, unfortunately they don't have every unit tested, but they have ample rated units and solid advice on the ones they have tested, hope this at least gets you started, feel free to ask any further questions.

I also use Corsair (depending on model, made by Seasonic or Channel Wells) as they are excellent and dead quite PSUs, but any PSU that is "80% plus certified" is worth consideration. The Antec brand is good, well regarded and cheaper than Corsair.

System builders and general computer users should be reminded that computer power requirements for most (equivalent) hardware from Displays to CPUs, has been going down over the years, not up. Quite dramatically in some areas.

Go to the link below for the best PSU calculator to work out accurately how much power you need. If you have no plans to run twin video cards at some stage, the OCZ StealthXstream II 500W PC Power Supply you mentioned would be fine for your current PC.

eXtreme Power Supply Calculator

Cheers,
Lee

Thanks Lee, The PSU calc you advised reckons I only need around 350 watts. I am going to go for the OCZ StealthXstream II 500W PC Power Supply as I won't be expanding my set-up further.

TBH as I said above I would avoid that unit as it's produced by FSP, I would go for the Corsair 500W CX V2 (PSUCMPSU-500CXV2UK) as it's got more connections and fractionally cheaper than your choice, even the conclusion in the link states the 400w OCZ unit of the same model is a much better buy than the 500w version, assuming 400w is enough for you, but the choice is yours.

Hi,I didn't realise that had more connections. I will go with the 500W CX V2 (PSUCMPSU-500CXV2UK) then based on your recommendation. I have searched around and £50 is the cheapest I've seen it,do you know anywhere cheaper? cheers. BTW thanks again for helping out!

Well both Ebuyer and Dabs have the unit listed at just under £45, with pennies between the 2, adding shipping on takes it to £48 odd, but with Ebuyer if you added something else to make it £50 + then shipping is free using the supersaver option, so if you need a spare thumb drive, or some disks you can save on the shipping cost, hope that helps.

TBH as I said above I would avoid that unit as it's produced by FSP, I would go for the Corsair 500W CX V2 (PSUCMPSU-500CXV2UK) as it's got more connections and fractionally cheaper than your choice, even the conclusion in the link states the 400w OCZ unit of the same model is a much better buy than the 500w version, assuming 400w is enough for you, but the choice is yours.

I'd go along with the Corsair 500W CX V2 8210GUY recommends if available for the for the price in your country, but they are $80-$100 here and apparently everything is not as it seems (sadly) with this line of Corsair CX power units http://www.overclock.net/t/837679/psa-the-corsair-cx-series

Are OCZ psu's any good?
I seen this one OCZ ZS Series 550W '80 Plus Bronze' Power Supply but it doesn't have any reviews
http://www.overclockers.co.uk/showproduct….123&subcat=

Well OCZ bought out PCP&C which are considered the best out there, so they certainly have access to quality builds, so I would say this is probably a good unit, a review I saw rated it well for a value unit, but one point they did make was that this unit has no floppy drive power lead, not an issue in new(er) builds, as people are not really using these anymore, but if you do need this feature on that build then this is not the unit for you, hope this helps a bit anyway.

You probably wouldn't miss a floppy drive connection on that OCZ PSU anyway, but if you ever do, there is a cheap and simple solution.

Molex to Floppy Drive Power Cable

An '80+bronze' certified PSU for the price, is great buying

Cheers,
Lee

Hi guys, I am going to take a chance on that psu. I don't have a floppy drive anyway so no problem there. Thanks to both of you for taking the time to give some advice.