Alright... So this is the first time I've built a computer. So far, I've connected everything in the computer to the correct ports. I recently plugged in all of the modular cables from the power supply to all of my components, preparing for my first boot of the system.
What works (I think):
1) The motherboard has a green light on it, which I'm assuming means it's receiving power.
2) My SSD has been plugged in, though I'm not sure how to tell if power is flowing to it.
3) My old 250 GB hard drive is connected, and I'm assuming it's working because I heard little clicks coming from it when I powered up.
4) All fans (video card fan included) spin, so I know they have power.
What doesn't work (I think?):
1) So where I seem to be lacking power is to my USB ports. I have some that are a part of my motherboard. I have some that are wired to the top of my computer case. And I also have some that I decided to plug into the back of the computer as additional USB slots. However, my optical mouse will not light up when it is plugged into the computer, which makes me wonder if it's receiving power to any of the USB ports. I also have a keyboard that lights up, which is not lighting up upon plugging into any of the ports.
2) My main concern - With monitor powered on, upon starting the machine, no BIOS screen ever appears. My monitor's blue power light continues to blink as if it were in sleep mode. When I disconnect the monitor from the video card, it tells me to check signal, and when I plug it back into the video card, it stays black again. This monitor has worked before (within the past week), and I'm 99.999% sure it's not an issue with a faulty monitor or anything like that.
Thank you in advance for any help you have to offer.
I did have concerns of the 750 watt power supply being too small for both of my Nvidia 470X 1.25 GB graphics cards, but I disconnected one of them in order to get the BIOS and everything running, and to negate any issues with a shortage of wattage. I had posted this on Yahoo Answers without a good reply... All I got was one guy asking me whether my monitor was plugged into my video card, or something else. When I told him that my monitor was plugged into a video card that was plugged into my mother board (PCI Express 16), I never got a response.
If your motherboard has an onboard VGA port in the back, I would suggest leaving out the video card at first. Connect your monitor to the VGA port on the motherboard. (by all the USB connectors, ethernet cable, and so on). I believe what is happening is the board is outputting video through the onboard VGA. once you hook up to that you can change the default video device in the BIOS and everything should be fine.
And so that we can better help you, Please post ALL computer components - brand names, model numbers of ram and make of motherboard, name, size of SSD and HDD. Things like that so we know what we're looking at.
Breadboard with just motherboard, CPU & HSF, case speaker, and PSU.
Make sure you plug the CPU power cable in. The system will not boot without it.
I always breadboard a new build. It takes only a few minutes, and you know you are putting good parts in the case once you are finished.
You can turn on the PC by momentarily shorting the two pins that the case power switch goes to. You should hear a series of long, single beeps indicating memory problems. Silence indicates a problem with (in most likely order) the PSU, motherboard, or CPU. Remember, at this time, you do not have a graphics card installed so the load on your PSU will be reduced.
If no beeps: Running fans and drives and motherboard LED's do not necessarily indicate a good PSU. In the absence of a single short beep, they also do not indicate that the system is booting.
At this point, you can sort of check the PSU. Try to borrow a known good PSU of around 550 - 600 watts. That will power just about any system with a single GPU. If you cannot do that, use a DMM to measure the voltages. Measure between the colored wires and either chassis ground or the black wires. Yellow wires should be 12 volts. Red wires: +5 volts, orange wires: +3.3 volts, blue wire : -12 volts, violet wire: 5 volts always on. Tolerances are +/- 5% except for the -12 volts which is +/- 10%.
The gray wire is really important. It should go from 0 to +5 volts when you turn the PSU on with the case switch. CPU needs this signal to boot.
A way that might be easier is to use the main power plug. Working from the back of the plug where the wires come out, use a bare paperclip to short between the green wire and one of the neighboring black wires. That will do the same thing with an installed PSU. It is also an easy way to bypass a questionable case power switch.
This checks the PSU under no load conditions, so it is not completely reliable. But if it can not pass this, it is dead. Then repeat the checks with the PSU plugged into the computer to put a load on the PSU.
If the system beeps:
If it looks like the PSU is good, install a memory stick. Boot. Beep pattern should change to one long and several short beeps indicating a missing graphics card.
Silence, long single beeps, or series of short beeps indicate a problem with the memory. If you get short beeps verify that the memory is in the appropriate motherboard slots.
Insert the video card and connect any necessary PCIe power connectors. Boot. At this point, the system should POST successfully (a single short beep). Notice that you do not need keyboard, mouse, monitor, or drives to successfully POST. At this point, if the system doesn't work, it's either the video card or an inadequate PSU. Or rarely - the motherboard's PCIe interface.
Now start connecting the rest of the devices starting with the monitor, then keyboard and mouse, then the rest of the devices, testing after each step. It's possible that you can pass the POST with a defective video card. The POST routines can only check the video interface. It cannot check the internal parts of the video card.