PSU & Motherboard questions

[Caudovittatus]

Hi all, got a quick question on PSUs...

How much power do you actually need? What I'm aiming at is a Core i7 920 (overclocked), 12Gb RAM, 2 new HDDs (and two old from a previous system), with either a 4870x2 or two 4890s or maybe two GeForce 260/275's (I may stick to a single card to start with, but definitely want the ability to go to two). I've been assuming that I'd need to get a pretty big PSU (800 - 850?) but I'm not sure how to go about calculating what I need.

I'd like to keep the cost as low as possible (to ensure that my budget does allow me to get the more interesting bits), but at the same time I definitely want something of quality (so I will let the spec of the system suffer if it needs to to ensure I get a PSU that's up to the task).

With that in mind what PSU would you recommend (makes and sizes)?


The motherboard question is simple: Asus P6T Deluxe V2 or Gigabyte EX58-UD5? They seem similar in many ways and I'm leaning towards the EX58, but I'd be interested in people's thoughts on these two, particularly if you've had direct experience of both.

[piggin23]

Try this

http://www.corsair.com/psufinder/default.aspx

[Blitzen]

Try this

http://www.corsair.com/psufinder/default.aspx

I wouldnt else it will just try and palm you off with a Corsair PSU.

A good brand 600W+ PSU would be more than enough.

I would head for this: http://www.scan.co.uk/Products/625W-...uard-SafeGuard

or this: http://www.scan.co.uk/Products/750w-...-1x-8pin-PCI-E

or this: http://www.scan.co.uk/Products/650W-...lar-PSU-87-Eff

[0iD]

Indeed, Enermax, Seasonic, etc

[peterb]

Generally less than ythe mfr calculators would have you believe.

A PSU is generally most efficient when it is at about 80% loaded, so ideally you should atch PSU to system.

However in practice the efficiency curves (on a good quality PSU) are fairly flat from about 50% loadin to about 80-85% so a PSU rated slightly higher than you need so that you have headroom as the system grows is no bad thing.

But unless you are running multiple GPUs and enormous numbers of disk drives, a 500 to 550W PSU should be adequate for the majority of PCS. (And if you are running a system with unusual hardware configurations, you need to look at the power capabilities of each rail of the PSU to make sure that the power delivery is delivered in the way that meets your system build requirement)

[MrMyst]

i only know that asus has a terrible slow rma service in uk, i met few guys who waited more than a month to get their mobos repaired