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DO I need to plug the 4 pin 12v
- Thread starter Chavito21
- Start date
OK, I'm going to join the debate on this because I just posed this question on another thread. I was looking at a specific Abit AMD motherboard that has the 4-pin P4 connector and I don't want to have to upgrade my power supply. Here's a link from Abit answering this question with regards to two of its boards (although the broken English is subject to interpretation):
I see it as saying that, though these boards have the extra connector, it doesn't have to be used if the power supply doesn't have it. I'm not sure if this would apply to the board mentioned above, but apparently it can be true for some boards.
I see it as saying that, though these boards have the extra connector, it doesn't have to be used if the power supply doesn't have it. I'm not sure if this would apply to the board mentioned above, but apparently it can be true for some boards.
The extra connectors were added at the order of the FCC to limit current through individual connectors to under 5A.
I would suspect that it would be OK to not have them connected on the slower chips of a family, but at higher speeds not having them connected may get voltage drop from the current requirements.
Ed Fair
Give the wrong symptoms, get the wrong solutions.
I would suspect that it would be OK to not have them connected on the slower chips of a family, but at higher speeds not having them connected may get voltage drop from the current requirements.
Ed Fair
Give the wrong symptoms, get the wrong solutions.
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- #6
legion2552
Technical User
Sounds like it doesn't have enough juice.
When troubleshooting my newish system, I used an older 350W/400W (can't remember exactly) just to check out whether I had PSU probs or not. The older one didn't have the 4 pin connector as opposed to my new PSU and I found SOME fans and the mobo fired up... although I quickly turned it off when I realised my CPU & mobo fans weren't running...
S
It may not be the same with you, but I would advise anyone who tries this to keep and eye on your fans. Watching ur CPU jump 20oC in around about a minute is brown trousers time...
When troubleshooting my newish system, I used an older 350W/400W (can't remember exactly) just to check out whether I had PSU probs or not. The older one didn't have the 4 pin connector as opposed to my new PSU and I found SOME fans and the mobo fired up... although I quickly turned it off when I realised my CPU & mobo fans weren't running...
SIt may not be the same with you, but I would advise anyone who tries this to keep and eye on your fans. Watching ur CPU jump 20oC in around about a minute is brown trousers time...
I recently owned a Gigabyte GA7-VAXP which didn't have the additional supply connector.
It burnt out 5 terminal connectors on the main power plug.
If this motherboard had got the additional connector I suspect this wouldn't have happened.
Motherboard supply demands have grown 2-3 times since the ATX connector was introduced and now just can't keep up with the extra demands put on it, hence the appearance of the extra connection to help relieve the loads carried by the main terminal block.
Martin
Replying helps further our knowledge, without comment leaves us wondering.
It burnt out 5 terminal connectors on the main power plug.
If this motherboard had got the additional connector I suspect this wouldn't have happened.
Motherboard supply demands have grown 2-3 times since the ATX connector was introduced and now just can't keep up with the extra demands put on it, hence the appearance of the extra connection to help relieve the loads carried by the main terminal block.
Martin
Replying helps further our knowledge, without comment leaves us wondering.
If you use a P4 CPU you definetely will need the 4 pin connector. It might boot up ok but the currents will be very high indeed. Depending on the speed of the P4 they could be as low as 30 amps or as high as 85 amps (actually measured). This is why Gigabyte now adds a plug in secondary supply to their top of the line main boards, this can deliver an additional 150 amps max for the 1.5 volt line. Greetings
Jurgen
Jurgen
Not 150 amps. You couldn't force 150 amps thru all the wires without having a Hollywood style searchlight.
Either the meter is defective or the multiplier is set wrong or you looked at the wrong scale.
Ed Fair
Give the wrong symptoms, get the wrong solutions.
Either the meter is defective or the multiplier is set wrong or you looked at the wrong scale.
Ed Fair
Give the wrong symptoms, get the wrong solutions.
- Thread starter
- #11
rclarke250
Technical User
Depends on the BIOS. power or memory error. Check that you have correct memory for board,and if it is in the first slot,some boards need this. Also check that your cpu fan is in the right spot.
: edfair
I said that some top MOBO manufacturers, on their top of the line boards have a plug in supply which can deliver up to 150 amps on the 1.5 volt line. It is a switch mode supply which uses its own specialised socket for connections. The other point (30 to 80 amps) are actually measured in our laboratory. You can work it out yourself. The P4 HT EE is rated by Intel from 80 watts to 122 watts power, depending on the usage. On the 1.5 volt supply 122 watts are equivalent to 81.2 amps, on the lower side, at idling the 80 watts current is still 53 amps. Modern processors use a hell of a lot of current, make no mistake about it. even a humble P4 HT 2.4 uses 63 watts at idling this is about 45 amps. Regards
Jurgen
I said that some top MOBO manufacturers, on their top of the line boards have a plug in supply which can deliver up to 150 amps on the 1.5 volt line. It is a switch mode supply which uses its own specialised socket for connections. The other point (30 to 80 amps) are actually measured in our laboratory. You can work it out yourself. The P4 HT EE is rated by Intel from 80 watts to 122 watts power, depending on the usage. On the 1.5 volt supply 122 watts are equivalent to 81.2 amps, on the lower side, at idling the 80 watts current is still 53 amps. Modern processors use a hell of a lot of current, make no mistake about it. even a humble P4 HT 2.4 uses 63 watts at idling this is about 45 amps. Regards
Jurgen
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- #14
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- #16
What is the processor you are using? And which is the speed of your CPU? Could be very simply that the new supply does not have enough current. Which wattage is the new supply rated? Suggest also to remove the cmoss battery so that you start with the fail safe defaults. Leave the battery out for at least 15 minutes also disconnect the power to the computer. Maybe this will help. Regards
Jurgen
Jurgen
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- #18
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