Looking for advice on PSU choice..

[collettnj]

Looking for some advice on PSU choice for the following system:

Gigabyte GA-EP45-DS5 (iP45 Express)
Intel E8500 - Looking to overclock this as much as I realistically can (Thermalright 120 eXtreme heatsink)
BFG 1GB GTX280 OCX
4GB OCZ PC2-8000 at 1000MHz
2x74GB WD Raptor HDD
1x750GB WD Caviar HDD
1xDVD/RW
4x120mm 2000RPM Sharkoon fans
7-8 USB devices, all of which rely on the computer for their power
Probably a sound card at some point
2.1 speakers

The various PSU calculator tools i've tried have come out at about 400-500W, though the BFG tech website says the following about the graphics card:

'575W PCI Express®-compliant system power supply with a combined 12V current rating of 42A or more (Minimum system power requirement based on a PC configured with an Intel Core®2 Extreme QX9650 processor)'


I'd guess I'm looking at at least a 700W power supply. I've searched around, but opinions vary considerably as to the best PSU for this kind of setup.

Will I be looking for a single 12V rail or multiple? A modular unit is vital for me as I don't have the biggest case.

http://www.scan.co.uk/Products/700W-...s80-Efficiency
http://www.scan.co.uk/Products/800W-...s80-Efficiency
http://www.scan.co.uk/Products/850W-...fficiency-RoHS
http://www.scan.co.uk/Products/850W-...ire-X-Quad-SLi

I've been looking at that lot...quite a variety of pricing there, and I'm no expert on PSU specs etc, so I'd appreciate some advice! Cheers..

(edit: On the mobo subject, what's the difference between the 'P45' and 'iP45 Express' chipsets?)

[staffsMike]

Something like the corsair 520W HX or enermax modu82+ is more than enough for the system above.

No difference between P45 and iP45 express as far as I am aware, just naming conventions I think.

[collettnj]

Are you sure 520 is sufficient for all that? My old PC had a lesser C2D with an 8800GTS, and was powered by a 600W, and had freezing issues accompanied by voltage drops (issues the same across 2 motherboards, several sets of ram, 2 different GPUs), which I could only pin on the PSU.

I'm looking for plenty of headroom for overclocking...of those that I linked to above, which would you say would be the best option?

[strike-down]

But what '600w' psu was it?? if its an el-cheapo then it is not gonna output 600w, and it will spew all kinds of horrible voltages into your kit

[moogle]

and it will spew all kinds of horrible voltages into your kit

don't forget the ripples!

[collettnj]

But what '600w' psu was it?? if its an el-cheapo then it is not gonna output 600w, and it will spew all kinds of horrible voltages into your kit

Sorry, I should have specified before:

https://www.aria.co.uk/Products/Comp...roductId=27046

[staffsMike]

I don't hear good things about thermtake tbh.

Around 500W good quality watts is more than enough for that system.

[collettnj]

Fair enough...that being a multiple (4?) rail setup I guess..

My only reservation is that I might end up with it freezing again and wonder 'does my PSU have enough grunt'. I trust what you're saying, though if you had to take a pick from the 700/800W PSUs I specified, which would be best?

[staffsMike]

Well if you must have more power then this
http://www.scan.co.uk/Products/620W-...ty-NEW-VERSION!

or the enermax modu82+ 625W then but honestly it isn't worth it you won't be pulling anywhere near that.

If Blitzen comes along he will tell you that his 625W modu82 is running a more hungry system than yours (X38, q6600 i think and 2x HD4870's).

[strike-down]

The HX520 would easily be enough for your system, but if you do want more power, go for the HX620
I havent been on hexus that long, but from what I've seen, staffsmike is VERY good at speccing PCs for people, Id go with him on it if I were you

[collettnj]

I'm just a bit confused at the fact that BFG gives a requirement for 575W for the GTX280 alone, and even a 625W PSU would leave very little extra for all the rest. I appreciate that the power requirements advertised by the manufacturers are not always spot on, though looking at the numbers, it doesn't seem to leave very much headroom so to speak.

Most of those I posted are in the price bracked of that enermax, and while I'm sure it affords very stable power, are there any from my list that stand out to you as a particularly good option?

(edit: sorry strike-down, you must have posted while I was typing; I'm not doubting staffsmike, I'm just a little confused as to the numbers)

[strike-down]

the graphics card manufacturers always overstate the power requirements to cover their own bums
And you must not forget, the QX9650 is a quad core, power hungry beast. And you are running a C2D

EDIT: the corsair you posted isnt modular, so that would be knocked off your list anyway

[staffsMike]

Sorry as above really. 575W is for the people that buy a PSU in a brown box which says 750W on it and costs them £15.

They have to account for the people that don't buy quality products.

[collettnj]

EDIT: the corsair you posted isnt modular, so that would be knocked off your list anyway

whups my bad..I'll take that one out

Sorry as above really. 575W is for the people that buy a PSU in a brown box which as 750W and costs them £15.

They have to account for the people that don't buy quality products.

I see...that makes more sense. Looks like the enermax 625 is probably the best option for me then. Cheers folks

[staffsMike]

change that 6 for a 5 and it's the best option

But if you want to be very very safe then the 625W is good

[strike-down]

No problem dude, but i still agree with staffsmike, 625w is overkill imo