Author Topic: Bloom (and other computer experts)... help! (Read 1164 times)

Dead Man Flying · « **on:** January 02, 2002, 05:46:00 PM »

Normally I consider myself an expert at diagnosing, fixing, or building computers, but I'm at the end of my rope on this one. Any advice is welcome.

About a week ago, the power supply on my system blew, and along with it took the motherboard and CPU. I ordered and received today an Athlon XP 1700 CPU, Abit KR7A-RAID motherboard, and 512MB of Crucial PC2100 RAM.
I also grabbed a new case and 400 Watt AMD-approved power supply.

Slapped it all together again in the new case, added my hard drive, CD-RW, video card (GeForce 2), sound card (Soundblaster Live! Value), and network card back in. Went to power the puppy up and... nothing. Not even the fans power up. A light on the motherboard indicates that it is receiving power, but that's about it.

Bad mobo?

Thanks for the help.

-- Todd/Leviathn

Kwan · « **Reply #1 on:** January 02, 2002, 05:48:00 PM »

Take everything but the videocard and memory OUT and try again...PS failure can sometimes damage other hardware...

If that doesn't work....look for a standoff on the new case shorting the motherboard...

Good Luck

[ 01-02-2002: Message edited by: Kwan ]

Raubvogel · « **Reply #2 on:** January 02, 2002, 06:11:00 PM »

Double check the case power switch lead. I spent most of 2 days pulling my hair out over my last system. It had the same symptom...LED on the mobo came on, but nothing else. Turned out the mobo was a bit odd, all the leads except the power switch were horizontal, power sw was vertical. I felt like a real git when I double checked the diagram and noticed it.

bloom25 · « **Reply #3 on:** January 02, 2002, 06:35:00 PM »

Check your manual (and if you can online) to find out where the power switch leads go. I'm nearly 100% certain this is the problem. (I don't know why, but I always accidently put the switch leads on the wrong pins the first time I set up a new system.) It may also turn out that you have a bad switch in the case.

Those ATX switches are simply a momentary switch, so you can easily eliminate a bad switch from the equation by just getting a paperclip (or something else metal) and quickly contacting the two pins together that the switch leads go to (remember, you only need to touch them for a split second). This should power up the system. BE VERY CAREFUL TO ONLY SHORT THE SWITCH PINS - the system will turn on immediately when you touch them.

If that doesn't work, your powersupply could be bad. (Yes, defective new supplies do happen.) Testing an ATX supply is a little bit tricky, but it can be done. First of all unplug all the power connectors in the system and take the power supply loose from the case. Now locate the large ATX power plug that goes to the motherboard directly. On the side of the connector with the little clip you will see a small green (99% of the time) wire near the center of the plug. Make sure to have the power switch on the back of the power supply on if it is present. Now you can actually attempt to turn on the powersupply by shorting the green and black wire immediately next to it together. As long as these two wires are connected the power supply should be on (i.e. fan running). If you have a voltmeter it would be a good idea to measure the voltage on an IDE power connector (hard drive/cd drive power connector) to ensure the powersupply is working. The wiring on these plugs is: Center 2 black wires are ground, yellow wire is 12V+, red wire is 5V+.

_____________________________ ________________

My guess is that it's as simple as the power switch leads being on the wrong pins. (USB header connectors often look identical to the jumper block for the reset switch, HD led, speaker, and power switch.)

Good luck!

2Late4U · « **Reply #4 on:** January 02, 2002, 06:35:00 PM »

Make sure the Power supply is set to 110 (if your in USA)...if its set at 220, ya wont get very far.

bloom25 · « **Reply #5 on:** January 02, 2002, 06:54:00 PM »

I looked up the manual for your board online (very nice manual actually) and the info you need is on page 2-13. The 2 connectors you are looking for are right next to the battery (as shown in the figures). On what they call PN1 is where the HD led, Power LED, and power switch leads go. (Also the sleep button, which I doubt you will use.)

The speaker and reset switch go on PN2.

Dead Man Flying · « **Reply #6 on:** January 02, 2002, 08:01:00 PM »

Okay, here's the progress report.

I have some experience with Abit motherboards, and my old one was a KT7. The various leads appear to plug into KR7A-RAID in exactly the same manner as they did in the KT7. I even took a digital photo of the leads on the old motherboard before disassembling so I'd put them in the correct places upon assembling a new motherboard. The manual on page 2-13 confirms that the older setup should match the newer setup. Alas, even with the power lead installed in what appears to be the correct way, the system still fails to power up. Here are a few other points that may aid the diagnosis:

1) Prior to purchasing the KR7A-RAID, I plugged my old motherboard into this case with a brand new 300 Watt PS. It would power up, but it wouldn't POST. One dead mobo. This tells me that the power switch lead probably isn't bad. I'm also fairly certain that the 300 Watt PS functioned properly.

2) After installing the KR7A-RAID with the newer 400 Watt PS, the system fails to power up. The various leads are plugged in according (as far as I can tell) to the manual specifications on page 2-13.

3) The system failed to power up after substituting the working 300 Watt PS as well. Same symptoms.

4) Both the brand new 300 Watt PS and the brand new 400 Watt PS are set to 115 and were turned on while testing.

Thanks for the advice so far, everyone! Very useful stuff.

-- Todd/Leviathn

jan · « **Reply #7 on:** January 02, 2002, 08:05:00 PM »

have you tried running the system w/ different ram sticks? there´s a reasonable chance they were binned by the electrical shock that fried your cpu & mobo.

Dead Man Flying · « **Reply #8 on:** January 02, 2002, 08:22:00 PM »

As an addendum to what I just wrote, here's an exact description of how the motherboard status LED indicators (D14, D16, and D17 as described on page 2-16 of the user manual) behave. When I turn the power supply on, D14 lights up yellow, indicating that the +5VSB is supplying power to the motherboard. When I hit the power switch, the D16 (power on indicator) briefly flashes green, and the D17 (reset indicator) briefly flashes red. After this, nothing happens.

I took Bloom's advice and used a spare jumper to short the power on pins. This caused the exact same thing to happen -- D16 and D17 flashed briefly, and nothing powered up.

-- Todd/Leviathn

Dead Man Flying · « **Reply #9 on:** January 02, 2002, 08:29:00 PM »

Quote

Originally posted by jan:
have you tried running the system w/ different ram sticks? there´s a reasonable chance they were binned by the electrical shock that fried your cpu & mobo.

I purchased brand new RAM for the motherboard, so that's probably not it. In my experience bad RAM shows up during the POST, but it usually doesn't hinder powering up or initiating the POST.

Frost · « **Reply #10 on:** January 02, 2002, 08:32:00 PM »

Many people are having problems with KR7A shorting out on standoffs or raised dimples designed for attaching the motherboard. Check to make sure that the only thing touch the motherboard is the standoffs you have screws into.

The AGP slot and the memory on this board take a good firm push to get into place. Most suggest you place your motherboard on a firm surface and push in the memory until it clicks into place.

Are you using one stick of 512? People are also reporting problems using one stick of 512 as well as any memory with a x4 configuration. This board apparently is a little fickle about memory.

I am very interested in your experience since I am waiting for my KR7A, 1700xp, 256MB Corsair and Antec 400w case

-ammo- · « **Reply #11 on:** January 02, 2002, 09:50:00 PM »

I have an epox board and had the same issue when I first powered mine up..I put it together and it was the first time. I was in panick mode. I called some friends and they thought maybe power supply. I pulled my hair out for several hours and kept going over the MB manual. I finally figured it out. One of the jumpers (clear CMOS) I had in the wrong pins. Soon as I put it in the other set of pins, she fired right up. I duno if this is your problem but wanted to share this with you anyway.

Gluck Levi

ammo

Eagler · « **Reply #12 on:** January 03, 2002, 08:15:00 AM »

last board I assembled was an IWILL XP333. I had to really cram the Crucial PC2100 ram into the slot, way past the white clips snapping closed around the stick. It wouldn't power up but I did get the beep error. But I take it you don't even get any beeps ...

Dead Man Flying · « **Reply #13 on:** January 03, 2002, 09:38:00 AM »

Quote

Originally posted by Eagler:
last board I assembled was an IWILL XP333. I had to really cram the Crucial PC2100 ram into the slot, way past the white clips snapping closed around the stick. It wouldn't power up but I did get the beep error. But I take it you don't even get any beeps ...

Nope, I don't get that far. The system won't power up the fans, and it won't perform the power on self-test (POST). I'm beginning to think more and more than maybe the motherboard is just DOA.

-- Todd/Leviathn

weazel · « **Reply #14 on:** January 03, 2002, 10:04:00 AM »

Try the following before you return it, remove it from the case and set it on the static free packaging it came in.

With only the RAM and video card in their slots hook the monitor & power supply up and try to start it by jumpering across the power switch pins with a screwdriver.

If it works then you have a short to ground problem.

When I got my K7S5A a few months ago I had a similar problem, I installed the mobo in 2 different towers thinking it was a power supply issue.

I tried it out of the case and it booted right away, I had to buy a SuperMicro full tower to make it work.

I didn't find any reason for the board to be shorting and have since used both of those towers to build systems for customers.