Brand New MB won't post. Please Help Me, I'm down to just three hairs left on my head

[racer2b]

I dyin' here folks. I've assembled a hand full of PC's in the last few years and I'm putting together one for my wife to use. I had an old Amptron 9600 with a 200MMX. I bought all new stuff to use with it. Brand new Inwin A500 case and new WD HD etc. I get it put toghether and the **** thing won't post. No error beeps either. I triple checked the jumpers (it was working when I took it out of my machine a year and a half ago. I bought a new battery, still no post. The CPU fan kicks on, so it's getting power. So, I buy a brand new Tyan for $40. I get it, set the jumpers and that MB doesn't post. Now I don't know what it is. Am I wrong or does a MB post even without a CPU? Maybe my jumpers are all wrong. Could someone explain, if the manual says jumper so and so 'open' is that with the little clip off or on both or what. It's been so long since I've messed with jumpers. (My OC Celery uses soft bios.) Any suggestions are greatly appreciated. Thanks

[steves]

Need a CPU for post. The only thing you might get on the monitor is the graphic card details as some cards put these out on their own after a reset.

[steves]

P.S Yes open is with the clip off.

[Rickee]

As your name suggest, let's slow things down.

First, a MB should POST without a CPU. It goes to the Bios, then the memory...

Now, I'm not sure if a MB will POST is the memory is bad and/or not correctly installed. Sometimes, you need to here a good 'click' to know that the memory is in place.

Second, 'open' means that the jumper is not connected (ie. the little clip is off).

Third, here is a guideline to consider:

1. Only install the Vid Card, the floppy, and the HD.

2. Looking at the diagram, the first thing to check is that your CPU is identified correctly. I hope that you do have an Intel(?) 200MMX, not the non-MMX one. Make sure that JP3A and JP3B is connected at 1-2 (for a 200MMX).

3. The DIMMS being used should be set to 3.3v (for SDRAM). JP4A/JP4B set to 2-3.

4. Jumpers DSW1 set the CPU and Bus Speed. Adjust for Multiplier 3 at 66 Mhz.

5. Jumpers DSW2 sets the voltage. Make sure to set it to 2.8 Volts.

6. Visit this site to see a detailed explanation of your Amptron board. I'm sure that Tyan will list theirs.

http://www.amptron.com/

[racer2b]

Thanks for the info everyone. I'm suprised I'm not getting error beep codes.
Here is some more info I've thought about since my original post.
1)The LED on the MB is coming on.
2) I've tried both of my monitors, they say they're not recieving from PC
3)I've tried all three of the video cards I have. An old Trident 2D, a 5 month old Banshee, and a brand new V3 3000. All of them work in my main rig. I'm not getting any video post, there is no out put to monitor.
4) The same thing is happening with my two day old Tyan MB as was happening with the Amptron. The Amptron came with the CPU and worked when I took it out out of my case. I threw 64MB (16x4) of old 72 pin Simms RAM. Could this RAM have gone bad? I'm suprised by that, these four sticks have been kickin around my house for four years.
5)Since I'm not getting any output to a monitor, am I looking at a jumper settings, or bad RAM? I'm at work right now but I'll try to remove the RAM and see if I get any error beeps when I get home tonight. I did notice that the case speaker cable is a two prong and the MB has three prongs for the speaker. I wonder if I'm just not hearing the error beeps. Thanks for all the help guys. I can't wait to get home and dig into this again. This is half the fun of assembling your own PC

[Rickee]

Okay, not to give misinformation but...

...the last time I did turn on a computer without a CPU (a few years ago) was when I had a Compaq P100 desktop. Since then, I've never did it again (and I have never had a bad CPU).

The computer did the memory count and even allowed you access to the bios (a blinking cursor on the top right of the screen).

Afterwards, there was some garbled text...

Do MB's, particularly Compaq, handle missing CPU's differently? Or was it an age thing?

I could have sworn that the doctor said I wasn't certifiable http://www.sysopt.com/forum/smile.gif.

[lrs]

I had the same problem eariler this week, I finally pulled all the cards except the video card, I even pull the cables to the serial, printer ports and usb port. I just had the mouse, keyboard, monitor, floppy and hard drive hooked up and it booted finally.

Hope this helps, Larry

[chc]

No processor, no POST. The POST is nothing of mystery, it is simply a routine burned into the BIOS designed to check the various fundamental components of the computer. It is CODE, and so absolutely requires a processor.

While the Power supply fan is getting juice, that says nothing about the supply for the mobo and other devices. Check your 5 and 12 volt lines on the connectors used for HD. Two inner (black) are ground, one outer is +5, the other +12. Not sure how mobo power connectors are wired. Does your power LED come on? Try pulling ALL the memory - should get a beep code if the thing has any life to it at all.

[This message has been edited by chc (edited 05-07-99).]

[MickMitani]

Rickee,

if your Compaq posted without a CPU, that would be the first pentium mobo I've heard of that does that. Pentium mobos won't post without ram, either. racer2b, is your ram SIMMs or DIMMs? If DIMMs, make sure the ram is fully in the socket - it takes more force than you might think.
Oh, yeah, one other thing, do you have the power connectors attached correctly? Remember, for AT power connectors, it's black on black.

[Stevo]

just one suggestion

Try only one ram module and try it in every slot not just bank 0. This somehow worked on a friends computer, 1 dimm in bank 3 got it going

also does it have case open detection?

[racer2b]

Thanks for all your help guys. I triple checked the jumpers and ripped out all the cards except the video, plugged in the keyboard and mouse and monitor and she fired right up. An hour later Win98 OEM was on my wife was setting her wallpaper. GAG! Now if to network it with my PC and teach her how to deathmatch!! WOO WOO!!

[Peter M]

Rickee (and others),

no computer whatsoever, be it 8086, 286, 386, 486, Pentium, PowerPC, MIPS, Alpha, ...
does _anything_ without a processor.

The mainboard just resets the components at poweron, which makes the processor start at a constant memory location, where the system's designers put a ROM (in x86 boxes, the BIOS).

Code execution starts here, and POST is part of it. Until POST, an x86 box has already come a long way, done RAM detection, PCI init, graphics card init ...

Bottom line: No CPU means no code executed, hence no POST. Not even beeps, as the PC speaker also is software operated.

Regards, Peter (who happens to be a BIOS developer for x86 systems)

[steves]

Rickee~Either you had to many magic mushrooms that day or your CPU had home kind of fault that allowed it to run for the first 60 seconds or until a specifc operation was performed (which is not inconceivable) http://www.sysopt.com/forum/wink.gif