Not sure about the sequence of events after you press the ON button. I have a Gigabyte GA-81HXP MoBo with a 2.8 P4, 512Gb RAMBUS. It suddenly decided not to boot. You press the button the fans start up, the power supply light comes on - and then everything goes off. As far as I can discover, as the supplies come up a 'power good' signal is sent from a chip on the MB to the PSU to maintain the supplies. All the supplies seem to coming up (checked with multimeter)but I'm not sure if the 'power good signal' is a pulse or a permanent voltage and if I can measure it or not. Common sense tells me that the PSU is overloaded so I changed the PSU for a 500 watt PSU with the same result. This meant there was a possible power line short to deck so I changed the MB! Same result! What do I do now? Any help would be greatly appreciated.
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Need a power supply expert 3
- Thread starter nob1
- Start date
This reply is to nob1.
I had exactly the same problem - the solution turned out to be twofold.
1. Reset the power supply by turning it off at the back and removing the supply lead, then press and hold the computers power on button for one minute. (This is with the motherboard connected to the power supply.
2. Remove the CPU heat sink, clean off the remains of the old pad. Put on a thin coating of silver grease. Replace the Heatsink, reconnect the fan.
As it happens I then just re-inserteted the video card and powered up - it came up - winged no boot device - I left it 15 mins. Powered down. Reconnected everything and it booted up just fine!
It seems you must have a good thermal connection between the CPU and the heatsink and the fan must be rotating - or something tells the power supply to shut down. This is to protect your CPU from being fried. You then have to tell the power supply you have done this - or it it shuts down immediately anyway!
Hope this helps you - do let us all know how it goes.
I had exactly the same problem - the solution turned out to be twofold.
1. Reset the power supply by turning it off at the back and removing the supply lead, then press and hold the computers power on button for one minute. (This is with the motherboard connected to the power supply.
2. Remove the CPU heat sink, clean off the remains of the old pad. Put on a thin coating of silver grease. Replace the Heatsink, reconnect the fan.
As it happens I then just re-inserteted the video card and powered up - it came up - winged no boot device - I left it 15 mins. Powered down. Reconnected everything and it booted up just fine!
It seems you must have a good thermal connection between the CPU and the heatsink and the fan must be rotating - or something tells the power supply to shut down. This is to protect your CPU from being fried. You then have to tell the power supply you have done this - or it it shuts down immediately anyway!
Hope this helps you - do let us all know how it goes.
stduc, i didnt mention that because i have done so in the past and pretty much got shot down over it. What i do instead, i have a power supply tester, which pretty much does the same thing. I unhook the main power at the mobo and connect the power supply tester to it and the power supply re-sets itself and all is ready to go. They cost $10 to $15 and i got mine at comp-usa but i believe they have them at best-buy as well. I was told the power supply was going bad if i had to do that, but i dont believe its true, i believe it has to be re-set somehow.
Good advice + great people = tek-tips
Good advice + great people = tek-tips
- Thread starter
- #43
jimbuddy
Technical User
- Aug 1, 2003
- 54
what are the power requirements for this mobo.
the ATX style is 20 pin with an additional 4 pin connector.
some of the new mobo's like mine use eps12v type which is 24 pin plus 8 pin. if you plug in an atx12v power supply to a mobo that requires more groceries you will have this issue.
jim
the ATX style is 20 pin with an additional 4 pin connector.
some of the new mobo's like mine use eps12v type which is 24 pin plus 8 pin. if you plug in an atx12v power supply to a mobo that requires more groceries you will have this issue.
jim
- Thread starter
- #45
beyondcurrent
Technical User
Speaking of RAM, is RD ram (the type being used in DELL business machines with hyper-threading technology) the best when it comes to performance?
rd ram,or rambus was the next improvement over sdram.
However, the owners of the patent wanted too much money from the sale of each stick, so others came up with ddr ram and now ddr is the ram of choice.
RD ram, or rambus ram is faster, likely even better. Its also more money, but worth it. When if first came out, i got an intel vc820 mobo with rd ram, fast little puter i built with it and i still have it. Its fast for a 900 mhz cpu!
Good advice + great people = tek-tips
However, the owners of the patent wanted too much money from the sale of each stick, so others came up with ddr ram and now ddr is the ram of choice.
RD ram, or rambus ram is faster, likely even better. Its also more money, but worth it. When if first came out, i got an intel vc820 mobo with rd ram, fast little puter i built with it and i still have it. Its fast for a 900 mhz cpu!
Good advice + great people = tek-tips
- Thread starter
- #48
Thanks Garebo for the bit on RAMBUS. It's exactly the reason why I want to get this MB working. My current machine is a 3Mhz P4, 2Gb Fast Ram, 2 WD Raptor in Raid 0 plus a couple of 160Gb data drives, Radeon 9800. Yet I'm convinced that old RAMBUS MB was faster with a 2.4GHz P4, 1Gb Rambus, couple 120Mb drives in raid 0 and the graphics card was so old I can't remember what it was!.
As for the bus about the power connectors, its not so much age as simply what power connectors are needed or required for a certain mobo and thats all there is to it.
Age doesnt have that much to do with it, same as the fact that you can use a very old atx power supply to power an AMD processor that doesnt require the 12 volt 4 pin connector that P4 requires. Of course, the power supply may or may not be up to the task as per its age and perhaps lower wattage, still, if its ok in that regards, then it still will work. Just an example of where age doesnt matter as much as required connections and connectors and needs of the mobo.
If i had that setup with rambus, i sure as heck would want it up and running. Im not as astute as a lot of the other people here, and im only being honest about it is all, but i do think the ddr instead of rambus is likely a loss for computer enthusiasts. From what i have read (as i dont really know beans about it from my own knowledge), rambus is much better, as in faster, than ddr. So we basically got cheated out of a superior piece of hardware being the standard. On the other hand, with there being so many varieties of ddr now around, what with dual channel and the different speeds, you have to wonder. All i know is every time i have a machine on my hands with rambus it just seems to run fast and stable!
Good advice + great people = tek-tips
Age doesnt have that much to do with it, same as the fact that you can use a very old atx power supply to power an AMD processor that doesnt require the 12 volt 4 pin connector that P4 requires. Of course, the power supply may or may not be up to the task as per its age and perhaps lower wattage, still, if its ok in that regards, then it still will work. Just an example of where age doesnt matter as much as required connections and connectors and needs of the mobo.
If i had that setup with rambus, i sure as heck would want it up and running. Im not as astute as a lot of the other people here, and im only being honest about it is all, but i do think the ddr instead of rambus is likely a loss for computer enthusiasts. From what i have read (as i dont really know beans about it from my own knowledge), rambus is much better, as in faster, than ddr. So we basically got cheated out of a superior piece of hardware being the standard. On the other hand, with there being so many varieties of ddr now around, what with dual channel and the different speeds, you have to wonder. All i know is every time i have a machine on my hands with rambus it just seems to run fast and stable!
Good advice + great people = tek-tips
- Thread starter
- #50
Well I've done everything mentioned in the many posts I've received, Both MBs do exactly the same thing. The only common thing now is the CPU and unfortunately I haven't got a spare P4 unless I take one out of another machine. I think I will get another MB. The only ones available seem to be Intel that take RAMBUS and they don't seem to have many features (i.e. RAID, USB2, 1394 etc.)
Thanks again for all the info - you were great.
Thanks again for all the info - you were great.
I thought that we narrowed the problem down to the cpu. Seems to me you already got a new mobo, right? Its not likely that two mobos wouldnt work and a third will.
I would get another cpu as its possible both mobos are good and the cpu is bad.
Seems to me that there are server boards you can use in a desktop that are newer and have rambus and the other features you are looking for. This is mentioned above, Dell is mentioned along with server boards and rambus. Perhaps a look over there or at the Intel site.
However, at this point, i am thinking its your cpu. Unless we are all missing some small point or item.
I dont know for sure, but you could try bringing the cpu to a shop and ask them if they can test it for you.
Also, there is a power supply tester that can be bought at best buy or compusa for around $10. You plug your power supply main mobo connector to it and if the power supply is good it will power up. Now this isnt a definitive ok on your power supply, but i have found that this little gadget re-sets your power supply. Sometimes, when there are problems with a machine the power supply gets jolted in such a way that it needs to be re-set. Another forum member stated this way to fix that:
"Reset the power supply by turning it off at the back and removing the supply lead, then press and hold the computers power on button for one minute. (This is with the motherboard connected to the power supply.)"
I just use my power supply tester to do that job. And thats the best use for it, other than to tell me if the power supply is simply fried beyond help. The fact that the tester turns it on only tells me there may be some hope for it, but its great for the other job, to re-set the power supply.
Good advice + great people = tek-tips
I would get another cpu as its possible both mobos are good and the cpu is bad.
Seems to me that there are server boards you can use in a desktop that are newer and have rambus and the other features you are looking for. This is mentioned above, Dell is mentioned along with server boards and rambus. Perhaps a look over there or at the Intel site.
However, at this point, i am thinking its your cpu. Unless we are all missing some small point or item.
I dont know for sure, but you could try bringing the cpu to a shop and ask them if they can test it for you.
Also, there is a power supply tester that can be bought at best buy or compusa for around $10. You plug your power supply main mobo connector to it and if the power supply is good it will power up. Now this isnt a definitive ok on your power supply, but i have found that this little gadget re-sets your power supply. Sometimes, when there are problems with a machine the power supply gets jolted in such a way that it needs to be re-set. Another forum member stated this way to fix that:
"Reset the power supply by turning it off at the back and removing the supply lead, then press and hold the computers power on button for one minute. (This is with the motherboard connected to the power supply.)"
I just use my power supply tester to do that job. And thats the best use for it, other than to tell me if the power supply is simply fried beyond help. The fact that the tester turns it on only tells me there may be some hope for it, but its great for the other job, to re-set the power supply.
Good advice + great people = tek-tips
- Thread starter
- #52
Hooray! It was the CPU. Replaced it with the 2.4 P4 from my wife's machine and it WORKED!!!! It's now setting up windows XP and I can see it's fast already.
Interestingly - I put the 2.8 CPU in another machine and it's running; BUT at 1.42MHz. What on earth is wrong with it?
Meanwhile I can't get my wife off my machine!
I found a PSU tester online - I've ordered one.
You guys are the best.
Interestingly - I put the 2.8 CPU in another machine and it's running; BUT at 1.42MHz. What on earth is wrong with it?
Meanwhile I can't get my wife off my machine!
I found a PSU tester online - I've ordered one.
You guys are the best.
I'm wondering if my Dad has the same problem as you nob1. My fix (posted last week) turned out to be temporary. PC died in the week. Dad powered it off, then later it wouldn't power up. I re-seated the heatsink this morning with fresh grease - reset the power supply - etc etc. It starts to boot, then powers itself off. Almost immediately. So I brought it back with me this afternoon.
What do people think. Replace the CPU and see if that fixes it? Then if not get a new mobo? Or the other way round? Or is life short enough and should I just get both at the same time? I am 99% sure it's not the power supply as it behaves the same with a spare one I have.
What do people think. Replace the CPU and see if that fixes it? Then if not get a new mobo? Or the other way round? Or is life short enough and should I just get both at the same time? I am 99% sure it's not the power supply as it behaves the same with a spare one I have.
stduc, no offence meant but you really need to make a fresh new post.
For one thing thats always the way to go.
For another, this post is so very long already its not gonna be viewed by too many people.
Most important, even though you may think its the same problem, it may very well not be, you need to post on your own with all details of your machine and what you have done and not done sorta thing.
Again, no offence, just advice.
Good advice + great people = tek-tips
For one thing thats always the way to go.
For another, this post is so very long already its not gonna be viewed by too many people.
Most important, even though you may think its the same problem, it may very well not be, you need to post on your own with all details of your machine and what you have done and not done sorta thing.
Again, no offence, just advice.
Good advice + great people = tek-tips
I figured right! I really try hard so its great to know when you are right for a change, lol. Just glad you are up and running!!
It pretty much had to be something to do with cpu, which is actually kinda rare here, its usually something else. Still not sure its something else as the cpu does work!!
nob1, right off the top i am thinking of the bios.
However, the bios for both your machines are likely fairly new, but check the numbers and dates of the bios on the machine that doesnt identify the cpu correctly.
Also, you can go to intel website and download, for free,
intel cpu identification tools. They will help us out here in this case.
Also check bios of both machines and report back.
Good advice + great people = tek-tips
It pretty much had to be something to do with cpu, which is actually kinda rare here, its usually something else. Still not sure its something else as the cpu does work!!
nob1, right off the top i am thinking of the bios.
However, the bios for both your machines are likely fairly new, but check the numbers and dates of the bios on the machine that doesnt identify the cpu correctly.
Also, you can go to intel website and download, for free,
intel cpu identification tools. They will help us out here in this case.
Also check bios of both machines and report back.
Good advice + great people = tek-tips
garebo (Vendor)No offence taken. new thread here!
- Thread starter
- #57
Sometimes you have to disable progs like zone alarm and other firewalls, and also popup stoppers sometimes have to be disabled. Sometimes you have to adjust cookie handling.
I have run into that a lot at MSI and Asus or Abit, i forget which.
Good advice + great people = tek-tips
I have run into that a lot at MSI and Asus or Abit, i forget which.
Good advice + great people = tek-tips
- Thread starter
- #59
I've got the latest BIOS for both motherboards. I have flashed the Intel 850E MB which has the dual BIOS feature and all went well. I have yet to do the Intel 845 board which only has a single BIOS The update is from F2 to F4, so not a lot of difference! I just hope it recognises the 2.8 CPU!
Well you seem to have plenty of advice.
In the shop here I've had similar problems and the Proccessor itself turned out to be bad.
In another case it was a short between the MB and the case, but you've already tested this theory out.
Best of luck!
In the shop here I've had similar problems and the Proccessor itself turned out to be bad.
In another case it was a short between the MB and the case, but you've already tested this theory out.
Best of luck!
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