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From: MN on 8 Jun 2010 15:51 I just completed assembling a computer. It is based upon the MSI MS-7265 mobo and Morex 6610 case (with 250 watt power supply). It is a mini-ITX computer and includes a SATA hard-drive, an IDE (PATA) CD/DVD burner and a 3.5" floppy. (The latter can come in handy, sometimes.) Needless to say, it was a tight fit, with the cables to the mobo the most difficult and tedious part -- especially the cable dressing. I was careful during assembly, using a grounded wrist strap-- especially when placing the memory strips, cpu, and CPU-fan onto the mobo. I had all the docs & info at my finger tips which was needed to correctly place the numerous connections to the mobo headers/connectors (e.g. SATA. IDE, USB, power button switch and LED, etc.). Well, I applied AC power to the computer with the case-cover off and NO connections to the monitor, mouse and keyboard. I expected to see the CPU fan running and some beeping since the was no mouse or keyboard connected. Much to my disappointment, NOTHING happened. So, I realized that I would have to diagnose what is wrong. First, I checked the AC-cord and made sure it was OK, and also connected the computer to different AC outlets -- to make sure that the AC input was OK. Then I measured voltages on the power-supply's 20-pin main ATX connector. I found the requisite standby 5 volts on pin 9 (purple wire) and pin 14 (green wire). This is correct with no signal from the mobo. Next, I need to JUMPER pins on the 20-pin ATX connector the simulate the mobo's OK signal to the power supply. I don't KNOW which pins to jumper to see if the power supply will output the other voltages on other pins. My pinout diagram just lists the pin #, wire color, and voltage value --so I can't determine which pins to jumper. I WANT TO BE SURE TO JUMPER THE CORRECT PINS! Please advise my of the pins to jumper, and other steps to perform in my diagnosis.
From: Paul on 8 Jun 2010 17:02 MN wrote: > I just completed assembling a computer. It is based upon the MSI MS-7265 > mobo and Morex 6610 case (with 250 watt power supply). It is a mini-ITX > computer and includes a SATA hard-drive, an IDE (PATA) CD/DVD burner and a > 3.5" floppy. (The latter can come in handy, sometimes.) > > Needless to say, it was a tight fit, with the cables to the mobo the most > difficult and tedious part -- especially the cable dressing. I was careful > during assembly, using a grounded wrist strap-- especially when placing the > memory strips, cpu, and CPU-fan onto the mobo. I had all the docs & info at > my finger tips which was needed to correctly place the numerous connections > to the mobo headers/connectors (e.g. SATA. IDE, USB, power button switch and > LED, etc.). > > Well, I applied AC power to the computer with the case-cover off and NO > connections to the monitor, mouse and keyboard. I expected to see the CPU > fan running and some beeping since the was no mouse or keyboard connected. > Much to my disappointment, NOTHING happened. So, I realized that I would > have to diagnose what is wrong. > > First, I checked the AC-cord and made sure it was OK, and also connected the > computer to different AC outlets -- to make sure that the AC input was OK. > Then I measured voltages on the power-supply's 20-pin main ATX connector. I > found the requisite standby 5 volts on pin 9 (purple wire) and pin 14 > (green wire). This is correct with no signal from the mobo. > > Next, I need to JUMPER pins on the 20-pin ATX connector the simulate the > mobo's OK signal to the power supply. I don't KNOW which pins to jumper to > see if the power supply will output the other voltages on other pins. My > pinout diagram just lists the pin #, wire color, and voltage value --so I > can't determine which pins to jumper. I WANT TO BE SURE TO JUMPER THE > CORRECT PINS! > > Please advise my of the pins to jumper, and other steps to perform in my > diagnosis. > > Jumper PS_ON# to COM, to turn on a supply. There are specs of various sorts here if you need them. The third spec is for 24 pin supplies. Grounding PS_ON# means "turn on please". http://web.archive.org/web/20030424061333/http://www.formfactors.org/developer/specs/atx/ATX_ATX12V_PS_1_1.pdf http://www.formfactors.org/developer/specs/atx/ATX12V_1_3dg.pdf http://www.formfactors.org/developer/specs/ATX12V_PSDG_2_2_public_br2.pdf ******* And don't be in too big of a rush when doing that! The thing is, when you jumper PS_ON# to COM, you defeat some safety features. Some motherboards are designed to turn off the computer, if they detect CPU overheat. Using the jumper method, means the motherboard can't turn off the supply when it wants to. I would set up the system on my work bench, and verify it works first. Then spend the tedious hours doing installation and cable dress and the like. I've done that for a few builds here, choosing to assemble the motherboard while it sits on a piece of cardboard (or a telephone book). I've actually had the Windows screen showing, while all the hardware was strewn about the bench. The most dangerous part of that method, is the fact the video card has no mechanical support (except for the slot connector). Don't allow any small kids in the work area, as they may pull out the video card or cable and ruin the card or motherboard. A slight tug on the video cable is all it takes. Check that your front power switch, is inserted on the correct two pins of the PANEL connector. You can also use a screwdriver tip, to momentarily contact the two PWR switch pins on the panel connector. The switch type is momentary contact, so a screwdriver tip, touched to the two pins in question, will simulate a power switch. But use extreme care when doing so. That technique is only practical, if you have clear, line of sight access, to the PANEL header, and can hit the two pins accurately. You don't want to short something else and ruin it. There is a difference between the two interfaces on the computer. The PWR switch pins on the PANEL header are momentary contact. Only a slight touch of the two pins, turns it on. The PS_ON# signal on the ATX power supply cable, is level sensitive. You have to keep a shunt to COM present, for as long as you want the supply to be running. A momentary contact there is not enough - PS_ON# needs a steady level. Paul
From: LSMFT on 8 Jun 2010 17:27 MN wrote: > I just completed assembling a computer. It is based upon the MSI MS-7265 > mobo and Morex 6610 case (with 250 watt power supply). It is a mini-ITX > computer and includes a SATA hard-drive, an IDE (PATA) CD/DVD burner and a > 3.5" floppy. (The latter can come in handy, sometimes.) > > Needless to say, it was a tight fit, with the cables to the mobo the most > difficult and tedious part -- especially the cable dressing. I was careful > during assembly, using a grounded wrist strap-- especially when placing the > memory strips, cpu, and CPU-fan onto the mobo. I had all the docs& info at > my finger tips which was needed to correctly place the numerous connections > to the mobo headers/connectors (e.g. SATA. IDE, USB, power button switch and > LED, etc.). > > Well, I applied AC power to the computer with the case-cover off and NO > connections to the monitor, mouse and keyboard. I expected to see the CPU > fan running and some beeping since the was no mouse or keyboard connected. > Much to my disappointment, NOTHING happened. So, I realized that I would > have to diagnose what is wrong. > > First, I checked the AC-cord and made sure it was OK, and also connected the > computer to different AC outlets -- to make sure that the AC input was OK. > Then I measured voltages on the power-supply's 20-pin main ATX connector. I > found the requisite standby 5 volts on pin 9 (purple wire) and pin 14 > (green wire). This is correct with no signal from the mobo. > > Next, I need to JUMPER pins on the 20-pin ATX connector the simulate the > mobo's OK signal to the power supply. I don't KNOW which pins to jumper to > see if the power supply will output the other voltages on other pins. My > pinout diagram just lists the pin #, wire color, and voltage value --so I > can't determine which pins to jumper. I WANT TO BE SURE TO JUMPER THE > CORRECT PINS! > > Please advise my of the pins to jumper, and other steps to perform in my > diagnosis. > > It's green and black. -- LSMFT I haven't spoken to my wife in 18 months. I don't like to interrupt her.
From: MN on 8 Jun 2010 18:34 Paul, Thanx for your prompt reply and VERY useful info. I did jumper PS_ON# to COM, to turn on the power supply. Then I measured the voltages at the 20-pin ATX power connector. They were ALL OK! Then I went to the 4-pin 12-volt power connector. AHA! This was NOT the12-volt power connector -- although it looked almost identical (but without the side latch). I was fooled since it was tie-wrapped close to the 20-pin ATX connector. I then "dug-out" the REAL 4-pin 12-volt power connector; it's voltages measured OK. Next, I removed the jumper and DVM, and I connected the 2 power connectors to the mobo. Then, I plugged-in the computer, and pressed the power on/power-off button. After a few seconds (that's long?), the on/off button "glowed blue" and the CD/DVD led started blinking like normal. Also, I could eject/retract the CD/DVD disk tray by pressing the appropriate button on the front faceplate of the CD/DVD. That's the GOOD news. However, when I pressed the power on/power-off button, "power did NOT go off' as indicated by the blue LED at the center of the the power on/power-off button. What does this mean? Also, the CPU fan did NOT rotate nor were there any audible beep codes. Of course, if the CPU was not running, the BIOS code would not execute and generate any beeps, etc. So, now what. Can we conclude that the CPU is NOT running as indicated by the CPU fan not rotating -- OR -- is the CPU fan not rotating because the temperature is not "hot enough"? I am really perplexed. I am glad that the PS is OK and also of the minor functionality as indicated by the CD/DVD activity, but I don't have a rational hypothesis where to proceed next. In other words "WHAT DO I DO NEXT"? to advance "from first base". Please advise. Regards, Marty ============================================================================ "Paul" <nospam(a)needed.com> wrote in message news:humb4d$333$1(a)news.eternal-september.org... > the following reply to MN's previous msg: > > Jumper PS_ON# to COM, to turn on a supply. There are specs of various > sorts > here if you need them. The third spec is for 24 pin supplies. Grounding > PS_ON# means "turn on please". > > http://web.archive.org/web/20030424061333/http://www.formfactors.org/developer/specs/atx/ATX_ATX12V_PS_1_1.pdf > > http://www.formfactors.org/developer/specs/atx/ATX12V_1_3dg.pdf > > http://www.formfactors.org/developer/specs/ATX12V_PSDG_2_2_public_br2.pdf > > ******* > > And don't be in too big of a rush when doing that! > > The thing is, when you jumper PS_ON# to COM, you defeat some > safety features. Some motherboards are designed to turn off > the computer, if they detect CPU overheat. Using the jumper > method, means the motherboard can't turn off the supply when > it wants to. > > I would set up the system on my work bench, and verify it works > first. Then spend the tedious hours doing installation and cable dress > and the like. I've done that for a few builds here, choosing to assemble > the motherboard while it sits on a piece of cardboard (or a telephone > book). > I've actually had the Windows screen showing, while all the hardware > was strewn about the bench. The most dangerous part of that method, > is the fact the video card has no mechanical support (except for the > slot connector). Don't allow any small kids in the work area, as they > may pull out the video card or cable and ruin the card or motherboard. > A slight tug on the video cable is all it takes. > > Check that your front power switch, is inserted on the correct two > pins of the PANEL connector. > > You can also use a screwdriver tip, to momentarily contact the two > PWR switch pins on the panel connector. The switch type is momentary > contact, so a screwdriver tip, touched to the two pins in question, > will simulate a power switch. But use extreme care when doing so. > That technique is only practical, if you have clear, line of > sight access, to the PANEL header, and can hit the two pins > accurately. You don't want to short something else and ruin it. > > There is a difference between the two interfaces on the computer. > The PWR switch pins on the PANEL header are momentary contact. > Only a slight touch of the two pins, turns it on. The PS_ON# > signal on the ATX power supply cable, is level sensitive. You > have to keep a shunt to COM present, for as long as you want > the supply to be running. A momentary contact there is not > enough - PS_ON# needs a steady level. > > Paul
From: MN on 8 Jun 2010 18:42
Thanx LSMFT, I did the jumpering. Please see my reply to Paul in my previous post to see where I am now. ====================================================================== "LSMFT" <boleyn7(a)aol.com> wrote in message news:yByPn.68090$Gx2.23495(a)newsfe20.iad... > MN wrote: >> I just completed assembling a computer. It is based upon the MSI MS-7265 >> mobo and Morex 6610 case (with 250 watt power supply). It is a mini-ITX >> computer and includes a SATA hard-drive, an IDE (PATA) CD/DVD burner and >> a >> 3.5" floppy. (The latter can come in handy, sometimes.) >> >> Needless to say, it was a tight fit, with the cables to the mobo the most >> difficult and tedious part -- especially the cable dressing. I was >> careful >> during assembly, using a grounded wrist strap-- especially when placing >> the >> memory strips, cpu, and CPU-fan onto the mobo. I had all the docs& info >> at >> my finger tips which was needed to correctly place the numerous >> connections >> to the mobo headers/connectors (e.g. SATA. IDE, USB, power button switch >> and >> LED, etc.). >> >> Well, I applied AC power to the computer with the case-cover off and NO >> connections to the monitor, mouse and keyboard. I expected to see the CPU >> fan running and some beeping since the was no mouse or keyboard >> connected. >> Much to my disappointment, NOTHING happened. So, I realized that I would >> have to diagnose what is wrong. >> >> First, I checked the AC-cord and made sure it was OK, and also connected >> the >> computer to different AC outlets -- to make sure that the AC input was >> OK. >> Then I measured voltages on the power-supply's 20-pin main ATX connector. >> I >> found the requisite standby 5 volts on pin 9 (purple wire) and pin 14 >> (green wire). This is correct with no signal from the mobo. >> >> Next, I need to JUMPER pins on the 20-pin ATX connector the simulate the >> mobo's OK signal to the power supply. I don't KNOW which pins to jumper >> to >> see if the power supply will output the other voltages on other pins. My >> pinout diagram just lists the pin #, wire color, and voltage value --so >> I >> can't determine which pins to jumper. I WANT TO BE SURE TO JUMPER THE >> CORRECT PINS! >> >> Please advise my of the pins to jumper, and other steps to perform >> in my >> diagnosis. >> >> > It's green and black. > > -- > LSMFT > > I haven't spoken to my wife in 18 months. > I don't like to interrupt her. |