RE: Re: PC PSU

["Malcolm Surgenor" <malcolm@xxxxxxxxxxxx>]

Thanks Keith, I do have a fair bit connected to this PC but I've tried the
PSU with just the 3 mobo connectors and the one hard drive and this makes
no
difference.  Interestingly with no hard drive at all nothing happens at
all.

The difference in amps between the two PSUs is only marked on the 12v rail.

They compare as:

QTechnology   +3.3v (30a)  +5v (30a)  +12v (29a)
Silentmaxx    +3.3v (29a)  +5v (36a)  +12v (19a)

I also note that their specs list Combined Maximum Output at +3.3v / +5v.
For the QTechnology it's 235w and for the Silentmaxx it's 276w.

Given the above I'd almost think that +12v figure for the SilentMaxx unit
is
a typo and may be 29a too(?).

Malcolm

-----Original Message-----
From: Keith Doxey [mailto:ukha@xxxxxxx]
Sent: 27 December 2004 11:48
To: ukha_d@xxxxxxx
Subject: RE: [ukha_d] Re: PC PSU


Hi Malcolm

> -----Original Message-----
> From: m_surgenor [mailto:malcolm@xxxxxxx]
>
> in another forum someone pointed out this difference between the two
> PSUs I'm using...
>
> Silentmaxx    12 volt = 19 amps
> QTechnology  12 volt = 29 amps
>
> Excuse my electrical ignorance but what's the significance of this??
> I'd always checked the wattage of PSUs before but never ampage.
>
> Malcolm
>

It means that the Silentmaxx PSU cant supply as much power on its 12V rail
as the QTechnology.

SilentMaxx = 12 * 19 = 228W

QTechnology = 12 * 29 = 348W

Check the ratings for the other rails as well. Particularly the 5V and 3.3V
rails as these will be the most heavily used by the Mobo.

Another thing to beware of is that the ratings given for each rail will be
the MAXIMUM for that rail. Often you CANT obtain the maximum output from
ALL
rails simultaneously.

Do you have lots of drives and other bits and bobs in the PC?

If you have lots of drives try disconnecting all but the boot drive and see
what happen. The surge required to start all the drives could be shutting
the PSU down.

HTH

Keith