Confused about PSU

Biscuiteer

Biscuiteer

Biscuiteer

Associate
Joined
4 Dec 2008
Posts
8
Hello all,

I'm in the process of speccing a new computer and have got a bit stuck on choosing a PSU. I've used several online calculators that I found links to on this forum and have come up with answers ranging from 350W to 650W. I know to go for a good quality one, but I'm none the wiser on what wattage I need. The sytem will look something like:

Intel Q9450
Asus P5Q Pro
4Gb DDR2 (Probably Ballistix)
4-5 Spinpoint SATA HDDs
1 IDE or SATA DVD writer
PCI-E Nvidia GTX 260
PCI Tv tuner card (probably)
PCI 56K Modem
Antec P182 Case

I intend to mildly/moderately overclock the system too. Would a 500W PSU be sufficient for this?

I've also noticed that a lot of the lower wattage PSUs only have 4 SATA connectors - is it ok to use molex to SATA adaptors to power additional SATA devices or is this frowned upon for any reason?

Finally, given that I intend to use the PSU in the bottom of an Antec P182 - where there'll be limited space above and below the PSU - would it be better to purchase a PSU with a rear fan to allow better airflow?

thanks,
B
 
500W would work, but it would be pushing the limits of it. Better off with 650W or so for this build, due to the amount of HDD's.
 
As EvilOne says, 500W will work fine, but you'll be pushing the limits of it, it's not much more expensive going for a 650W one, though personally I'd recommend a 750W PSU.
 
Biscuiteer said:
Hello all,


I've also noticed that a lot of the lower wattage PSUs only have 4 SATA connectors - is it ok to use molex to SATA adaptors to power additional SATA devices or is this frowned upon for any reason?

Finally, given that I intend to use the PSU in the bottom of an Antec P182 - where there'll be limited space above and below the PSU - would it be better to purchase a PSU with a rear fan to allow better airflow?

thanks,
B
Click to expand...


You may run out of molex's too if your powering any fans and an ide dvd from them, but in principle using molex to sata power is fine as the voltages and currents are very low making the resistance from the cable join pretty irrelevant.

I think on that case the psu chamber should be treated as a separate cooling zone so rear fan psu would match air flow in from the front of the case and the drives there. PSU with bottom side fan would tend to pull hot air down from the mobo chamber, would work fo compoentns there but disturb airflow from front to rear.
 
As a little comment I'd suggest you go for the SATA optical drive. IDE is pretty much obsolete these days, and the cables are a PITA to route compared to SATAs, you no longer pay a significant premium for a SATA optical drive.
 
I agree with Malazan, you're right in the sweet spot for PSUs and have a whole range to choose from. The Corsair being on offer this week I think swings it.

OcUK don't sell crap PSUs as a general rule though, so you don't need to worry too much about whichever you choose.
 
I'd get a modular PSU, e.g. Corsair HX620. I have one and i'm glad I went modular, it's a whole lot easier and cleaner.
 
Thanks for all the replies guys, I'm going to go for the Corsair that's on special offer. It was on the shorlist of higher-wattage PSUs I'd compiled anyway and your recommendations have persuaded me to buy it.

Not sure that I want to pay the extra for the modular version as I think that I'll be using most of the connectors provided and I'm not getting a windowed case either.

The modem's just in there to get me through the annual **** up in a telephone exchange btw - I do have broadband. I just hope that it makes the transition to Vista with this build
 
You must log in or register to reply here.
Back
Top Bottom