In article , "Pete"
wrote:

I have just bought a Ultra Xconnect power supply 400watts to use in
conjunction with a AMD 3500+ and skt 939 board.

Here it is:

http://www.ultraproducts.com/product...roductID=3 04

It says it supports Pentium 4 and AMD CPUs and meets ATX version 2.03 and
ATX 12V version 1.2 specification.

When I bought it I thought it was the dogs ******** but now I see
motherboards with 24 pin PSU connectors and wonder what's going on.


Have I bought a lemon? Is it out of date? Has the ATX spec moved on?

Can you plug a 20pin ATX connector from the power supply onto a 24pin
connector on the motherboard and then use a 4 pin lead for the remaining 4
pins or would I need a convertor?


The motherboard I want to use it with has the following connectors:

24-pin ATX Power connector
4-pin ATX 12V Power connector

Would I need to buy extra cables / convertors to use it with this board?

Thanks

Pete

----- ATX 2.0+ main connector ----- --- ATX previous versions ---

Pin Signal Color Pin Signal Color Pin Signal Color Pin Signal Color
1 +3.3VDC Orange 13 +3.3VDC Orange 1 +3.3VDC Orange 11 +3.3VDC Orange
2 +3.3VDC Orange 14 -12VDC Blue 2 +3.3VDC Orange 12 -12VDC Blue
3 COM Black 15 COM Black 3 COM Black 13 COM Black
4 +5VDC Red 16 PS_ON# Green 4 +5VDC Red 14 PS_ON# Green
5 COM Black 17 COM Black 5 COM Black 15 COM Black
6 +5VDC Red 18 COM Black 6 +5VDC Red 16 COM Black
7 COM Black 19 COM Black 7 COM Black 17 COM Black
8 PWR_OK Gray 20 Reserved N/C 8 PWR_OK Gray 18 Reserved
N/C (-5V)
9 +5VSB Purple 21 +5VDC Red 9 +5VSB Purple 19 +5VDC Red
10 +12V1DC Yellow 22 +5VDC Red 10 +12VDC Yellow 20 +5VDC Red
11 +12V1DC Yellow 23 +5VDC Red
12 +3.3 VDC Orange 24 COM Black

--- ATX 2.0+ 12V for proc ------ --- ATX previous versions ---
Pin Signal Color Pin Signal Color Pin Signal Color Pin Signal Color
1 COM Black 3 +12V2DC Yellow/Black 1 COM Black 3 +12VDC Yellow
2 COM Black 4 +12V2DC Yellow/Black 2 COM Black 4 +12VDC Yellow

Changes:

1) -5V removed, prev supplies probably had it. Usually not an issue.
2) Four addition pins on main connector. Extra +3.3V, +5V, +12V, GND
Helps with PCI Express motherboards. For SLI boards, 24 pin
recommended (to get two 6 amp pins to feed the two video cards via
PCI Express slot connectors). For single video card, 20 pin is
generally enough. 6600GT for example, draws 4 amps. Xbitlabs.com has
measured many cards. If in doubt, do a detailed calculation.
3) 12V output split into two separate 12V circuits.
No advantage to customer, due to need to allocate extra "slack" when buying.
Perhaps intended to meet IEC60950 ? (To limit max power per 12V output)
12V1 feeds disks and motherboard (and video card)
12V2 used exclusively for processor (in your computer, that would be 8.24A)

* 24 pin can plug to 20 pin mobo, as long as pins don't bump
20 pin can plug to 24 pin mobo (same pinout) - use the right holes.
Some 24 pin are detachable, into a 20 pin part and a detached 4 pin part.
At least one guy has managed to plug the detached 4 pin, into the processor
Vcore input. (I haven't checked to see how hard that is to do.)

PCI Express slots have 12V pins on them and allow up to 5 amps.
Video cards (not overclocked) seem to be designed to draw about 4 amps
or a tiny bit more, through the PCI Express x16 slot. The single 12V
wire on the 20 pin connector carries at least 6 amps, so using a
20 pin connector on a non-SLI board seems reasonable. The fan header
current also flows through the single 12V pin on the 20 pin connector.

Main connector rated for 6 amps per pin.
http://www.molex.com/cgi-bin/bv/mole...roductID=98716

12V processor power connect pins rated at 8 amps per pin.
http://www.molex.com/cgi-bin/bv/mole...roductID=76873

Molex disk drive connector rated at 8 amps per pin (based on assuming
a right angle PCB mount connector, and 18 gauge wire - Amp 82181 catalog)

Enjoy your new power supply. No need for adapters.

The Ultra you have selected, has 12V @ 16A. If you had an 89W AMD
processor, that is (89W/12V)/0.90 = 8.24A. A midrange video card like
6600GT is 4A. That is 12.24 amps so far. A disk drive idles at 0.5A.
A CDROM can draw 1.5A according to the rating on the label. Allocate
0.5A for some fans. We are now at 14.74 amps of 16A. Your new Ultra
is suitable for a midrange gamer with minimal storage devices. More
than 16 amps is required if your PC has more toys in it. For example,
if you bought an ATI X1900XTX, it draws 10 amps (part through the
PCI Express slot, part through the 2x3 PCI Express connector), and
you would need about 12V @ 23A to have a stable computer. So, enjoy
your new Ultra, but do not overload it.

HTH,
Paul