i have an old compaq presario 5310US model....now i wanna buy a new case for it but the only problem that bothers me is how am i gonna plug up all the wires correctly so when i press the power button it'll turn on....on the original case its just one whole plug that looks like the internal usb plugs where u plug in onto the motherboard (on newer motherboards that is)....now if i buy a new case and im sure they usually come with all the wires just laying around and you gotta figure out how to put it in correctly if you have the manual....but i looked in the manual online and it said nothing about it....also is there a case out there that still uses that one big plug and you just plug it up ready to go??..i notice how if you have a power button and a restart button it usually is with alot of wires and you gotta plug it in correctly....but if its just the power button itself its one big plug and you just plug it in....so if anyone can help me out on this please let me know thanks....

DELL's quite often use proprietary Cases and PSU's, I would check very carefully that the Motherboard adheres to the ATX standard.

http://h10025.www1.hp.com/ewfrf/wc/...

http://en.wikipedia.org/wiki/ATX

It is time to be a detective. In your existing case trace the wires from the plug to where it is connected. The main ones are the power switch, the power led, the hard disk led, the speaker. Other possible connections especially in older cases are reset switch, turbo switch (usually 3 wires), turbo led, keyboard lock switch.

With your new case do the same.

When you mount you motherboard in your new case, just connect the wires to the pins in the corresponding position.

The first one should be the power switch connection. Next are the led's, power and hard drive. Then the speaker. The led's are the only ones that are polarity sensitive. If they don't work, swap the connections.

You only need the power switch to run the system.

"i have an old compaq presario 5310US model..."
"....on the original case its just one whole plug...'
"i looked in the manual online and it said nothing about it...."

That is usually the case for cases supplied with brand name systems. I think they make the connector one piece so that it is idiot proof for those that assemble computers, and that saves a tiny amount of time when assebling them. There is almost always no info about the front panel pinouts in the brand name system model's manuals - I don't know why that is - unless they expect people that buy their systems are unlikely to ever have another mboard in the same case, or are likely never going to put the same mboard in a generic case.
Generic cases do not have one piece connectors because the front panel pinouts vary from one mboard maker to another.

You could do as wizard fred sugggests - there may be abbreviations printed on the mboard beside the front panel header that give you clues, or there may be a list for that printed on the surface of the mboard.

Or if you can determine what mboard maker made the mboard, you may be able to find that makers manual for the same mboard or a very similar one that will have the front panel pinouts in it.
Most of the brand name system builders (other than e.g. Intel and Toshiba) do not make their own mboards - they are supplied to them OEM by mboard makers. Sometimes the brand name system builder will specify a special front panel pinout header that conforms to the pinouts for one piece connectors they use for other mboards, but often the front panel pinouts are exactly the same as retail models made by the same mboard maker that were made around the same time.

I looked up the HP parts for Presario 5310US.
It can have either a Celeron or an AMD K7 motherboard.
If it has a Celeron mboard, it has either of these two mboards:
5310US (Celeron) - (BBXZ) (470020-352) or (JXDS) (470022-125)

Loretto

http://partsurfer.hp.com/cgi-bin/sp...
http://partsurfer.hp.com/cgi-bin/sp...

If that's what you have
Searched for loretto
http://www.igs.net/~ndaines/Qfiles/...
This motherboard is an OEM version of the Lite-On TR100

Lite-On Support Pages:
http://www.liteontc.com.tw
I looked there - it seems there is no longer any info for older mboards.

A third party site has the information.
Manual, etc.
Go here:
http://www.elhvb.com/mobokive/Archi...
......

If it has an AMD K7 cpu (slot A)

NOTE that it is quite likely the pinouts for the front panel are the same as for the 5310 (Celeron) models - if all you need is the info for that, look at the TR100 manual, above.

If you would like to see if I can find a mboard maker's manual........

5310US (AMD) - (BBYZ) (470018-936) - mboard 232148-004 - no picture

Look for a label on the mboard with a name on it - e.g. ASPEN2, and/or an obvious model number printed on the mboard - often between the slots - tell me what you find.

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