mockingbird wrote on 2023-10-18, 23:51:

Ah, my mistake, it is the AK77-333 I own... You mean T-Bred, not T-Bird, big difference. […]
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Ah, my mistake, it is the AK77-333 I own... You mean T-Bred, not T-Bird, big difference.

But I have some advice for you nevertheless:

1) Get *any* thoroughbred you want, doesn't matter which, and mod it to a Mobile. I've done this, works perfectly fine.
2) Use bios patcher on your BIOS. Only do this if you have an external programmer so you can revert back. Use the switch that disables the backup feature or you might have issues.
3) Use the pin mod guide to figure out the multiplier you want and then solder the wires on the back of the PCB

With this method you get great flexibility... Forget about 133Mhz FSB, that doesn't offer any benefit with the measly SDRAM. Just do something like 100 * 18 for 1.8Ghz on something like a AXDA2200DKV3C which is widely available for next to nothing.

But you need the skills for this...

There is Thunderbird with a bus at 266, https://www.cpu-world.com/CPUs/K7/AMD-Athlon% … A1333AMS3C.html
Years ago I did the thing of forcing the multiplier, at the time it was 20x100 for 2000Mhz on a Compaq uwave motherboard, KT133 with a very limited BIOS. But I have another boards so I dont care about it.

shevalier wrote on 2023-10-19, 07:10:

Well I see some mistakes. On yellow boards, capacitors with blue markings do not look good - only with red and black ones. On bl […]
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Well I see some mistakes. On yellow boards, capacitors with blue markings do not look good - only with red and black ones.
On blue ones - everything except with green markings.
And everything is fine. 😀
Because everything else is "urban legends" about the instability of the voltage regulator.

PS. My gigabyte S754 had instability in the memory power regulator. There was instability with polymer capacitors. There was instability with electrolytic capacitors, there was instability without capacitors.
Because the designer added extra transistors for S1/S3 energy saving states.
It was the extra ones, I had to be simulated its in Microcap.

It is possible that the color of the capacitors causes instability, you may be right. I'll try some capacitors with RGB LEDs next time. Although that will cause instability for me, I have epilepsy. 😉 😀:)

Hoping wrote on 2023-10-19, 09:37:

It is possible that the color of the capacitors causes instability, you may be right. I'll try some capacitors with RGB LEDs next time. Although that will cause instability for me, I have epilepsy. 😉 😀:)

+100 point to stability

In fact, the frequency correction of the error amplifier's negative feedback depends on both capacitance and ESR.
But no one uses the perfect setting because as capacitors age, the capacitance drops. And in a year you can get instability.
In real life - from 0.5 to 2x from the original capacity with approximately equal to the original ESR.
Well, and the color matches the PCB.

PS. You really shouldn't put polymer capacitors near the audio codec because they sound bad. Because polymer ones have a very curved behavior of the permissible current versus frequency.

shevalier wrote on 2023-10-19, 09:53:

Well, and the color matches the PCB.

For example
-Why was Jetway K8T8As unstable?
Because the wrong transistor was used to power the HyperTransport.
Because the color of the capacitors did not match well with the color of the PCB.
Blue goes well with green, so the motherboard works well.
If these were green Samwha FB, then the motherboard would work perfectly.
-Why didn't the Radeon HD2600Pro AGP work at standard frequencies, but now runs great when overclocked?
Because Sapphire engineers soldering the frequency compensation circuit of the GPU power controller in the wrong pad.
Because blue on blue is just perfect
-Why does the Audigy SB0610 sound worse than the first version of the SB0400?
Because there was no need to plug extra electrolytic capacitors into the signal circuits.
Because dark brown goes perfectly with red.

And who will now argue that the color of the capacitors does not matter?
PS. The Audigy didn’t turn out to be very monochromatic, but I’m too lazy to redo it.
Because the result has been achieved.

shevalier wrote on 2023-10-19, 13:41:

For example -Why was Jetway K8T8As unstable? Because the wrong transistor was used to power the HyperTransport. Because the colo […]
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shevalier wrote on 2023-10-19, 09:53:

Well, and the color matches the PCB.

For example
-Why was Jetway K8T8As unstable?
Because the wrong transistor was used to power the HyperTransport.
Because the color of the capacitors did not match well with the color of the PCB.
Blue goes well with green, so the motherboard works well.
If these were green Samwha FB, then the motherboard would work perfectly.
-Why didn't the Radeon HD2600Pro AGP work at standard frequencies, but now runs great when overclocked?
Because Sapphire engineers soldering the frequency compensation circuit of the GPU power controller in the wrong pad.
Because blue on blue is just perfect
-Why does the Audigy SB0610 sound worse than the first version of the SB0400?
Because there was no need to plug extra electrolytic capacitors into the signal circuits.
Because dark brown goes perfectly with red.

And who will now argue that the color of the capacitors does not matter?
PS. The Audigy didn’t turn out to be very monochromatic, but I’m too lazy to redo it.
Because the result has been achieved.

Now, this is finally some top level engineering analysis, which is typically missing from this site!

🤣

CharlieFoxtrot wrote on 2023-10-19, 14:35:

shevalier wrote on 2023-10-19, 09:53:

For example
-Why was Jetway K8T8As unstable?
Because the wrong transistor was used to power the HyperTransport.

Now, this is finally some top level engineering analysis, which is typically missing from this site!

🤣

The board contains an integrated controller for power supply and voltage supply sequence of the motherboard. Therefore, powering the HyperTransport (1.2V) from the AGP+northbridge_core (1.5V) makes no sense at all. The HyperTransport power supply will appear later than the AGP power supply. Initially, there was a MOSFET with an Rds of 100 mOhm, which gives us at peak (1.5-1.2)/0.1 = 3 Amperes.
According to the specification for HyperTransport, this is enough, there is 2 Amperes (from memory)
In practice it turned out not to be the case. A MOSFET with an Rds of 30 mOhm is the solution to the problem.
Also, the idea of ​​controlling the voltage by connecting additional resistors in feedback directly to the GPIO is quite flawed.
This results in increased noise from the GPIO pin itself into the powered circuit.

Who needs this?
The motherboard is quite rare, and no one will resolder the transistors.
Therefore, at the blue PCB should have either green or blue polymer capacitors.

Or so?
Why, if no one will repeat it?

shevalier wrote on 2023-10-19, 07:10:

Well I see some mistakes. On yellow boards, capacitors with blue markings do not look good - only with red and black ones. On bl […]
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Hoping wrote on 2023-10-17, 14:15:

I repeat that I am not an electronic engineer

Well I see some mistakes. On yellow boards, capacitors with blue markings do not look good - only with red and black ones.
On blue ones - everything except with green markings.
And everything is fine. 😀
Because everything else is "urban legends" about the instability of the voltage regulator.

PS. My gigabyte S754 had instability in the memory power regulator. There was instability with polymer capacitors. There was instability with electrolytic capacitors, there was instability without capacitors.
Because the designer added extra transistors for S1/S3 energy saving states.
It was the extra ones, I had to be simulated its in Microcap.

Can you expand on what you did to solve the instabilities of the memory and the microcap is?

Cheers,

pentiumspeed wrote on 2023-10-19, 15:20:

shevalier wrote on 2023-10-19, 07:10:

Well I see some mistakes. On yellow boards, capacitors with blue markings do not look good - only with red and black ones. On bl […]
Show full quote

Hoping wrote on 2023-10-17, 14:15:

I repeat that I am not an electronic engineer

Well I see some mistakes. On yellow boards, capacitors with blue markings do not look good - only with red and black ones.
On blue ones - everything except with green markings.
And everything is fine. 😀
Because everything else is "urban legends" about the instability of the voltage regulator.

PS. My gigabyte S754 had instability in the memory power regulator. There was instability with polymer capacitors. There was instability with electrolytic capacitors, there was instability without capacitors.
Because the designer added extra transistors for S1/S3 energy saving states.
It was the extra ones, I had to be simulated its in Microcap.

Can you expand on what you did to solve the instabilities of the memory and the microcap is?

Cheers,

see screenshots above in the post.
Q26,27,28 are extra.
They try to duplicate Q21,22,23,25, which change the reference voltage for the memory regulator depending on the S3/S5 power state.
And they (Q26 to ground) break off negative feedback, which in itself is nonsense.
At the same time, being in a semi-active state, these extra transistors the noise from the GPIO.
Which leads to oscillations of 150-200mVolt.

PS. This motherboard was made by me for audio measurements and I absolutely did not need a 30 dB needle at a frequency of 13 kHz at spectrograms.
Now I'm playing Dungeon Keeper 2 with Diamond Monster MX300 on this motherboard 😀
Because I’m tired of audio development as a hobby.

shevalier wrote on 2023-10-19, 09:53:

+100 point to stability https://www.vogons.org/download/file.php?id=159601&mode=view […]
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Hoping wrote on 2023-10-19, 09:37:

It is possible that the color of the capacitors causes instability, you may be right. I'll try some capacitors with RGB LEDs next time. Although that will cause instability for me, I have epilepsy. 😉 😀:)

+100 point to stability

In fact, the frequency correction of the error amplifier's negative feedback depends on both capacitance and ESR.
But no one uses the perfect setting because as capacitors age, the capacitance drops. And in a year you can get instability.
In real life - from 0.5 to 2x from the original capacity with approximately equal to the original ESR.
Well, and the color matches the PCB.

PS. You really shouldn't put polymer capacitors near the audio codec because they sound bad. Because polymer ones have a very curved behavior of the permissible current versus frequency.

Is this your motherboard in this picture (the blue one)?

I consider all boards with heavy power (those AMD and P4 CPUs) using 2 phase VRM insufficient and I had instability in past. When I moved on to boards with 3 phases or more, I had stability back. 2 phase VRM is also make more noise if you are all about quality of audio. 3 phase and at least 5 to 6 bigger diameter capacitors, not the smaller ones and lot more MLCC capacitors.

How I know? I had socket 462 board with 2 phase VRM and was unstable and to add more, what bad enough is using linear regualators to supply 3.3V to AGP slot too. By the way, this I was not about overclocking also.

Cheers,

shevalier wrote on 2023-10-19, 13:41:

For example -Why was Jetway K8T8As unstable? Because the wrong transistor was used to power the HyperTransport. Because the colo […]
Show full quote

For example
-Why was Jetway K8T8As unstable?
Because the wrong transistor was used to power the HyperTransport.
Because the color of the capacitors did not match well with the color of the PCB.
Blue goes well with green, so the motherboard works well.
If these were green Samwha FB, then the motherboard would work perfectly.
-Why didn't the Radeon HD2600Pro AGP work at standard frequencies, but now runs great when overclocked?
Because Sapphire engineers soldering the frequency compensation circuit of the GPU power controller in the wrong pad.
Because blue on blue is just perfect
-Why does the Audigy SB0610 sound worse than the first version of the SB0400?
Because there was no need to plug extra electrolytic capacitors into the signal circuits.
Because dark brown goes perfectly with red.

And who will now argue that the color of the capacitors does not matter?
PS. The Audigy didn’t turn out to be very monochromatic, but I’m too lazy to redo it.
Because the result has been achieved.

EPIC post! +100 !!!!!

@shevalier.
Appearance doesn't matter to me at all, I prioritize performance.
But above all, thank you very much for the explanations.
It would be interesting to have a calm, detailed explanation, avoiding technicalities as much as possible, about the real importance of ESR and even ESL, and also why a high capacitance is not the most important thing, and the reason why the more expensive the hardware is, more MLCCs and SMD polymer capacitors instead of radial ones you find; An example that I know personally is the Fujitsu D3128-b25 that uses many fewer radial capacitors than are usually seen in the VRM, but on the back it has several SMD polymers.
The PCBONEZ explanation I mentioned above was very good, but I think that anyone paid much attention to it.
I can't explain those details because I have no idea.
There will be those who will say that I am something like a heretic. 😀

mockingbird wrote on 2023-10-19, 16:37:

EPIC post! +100 !!!!!

It's not as funny as it seems.
In the beginning, everyone sculpted anything. For example, Gigabyte

And it looked ugly
Then they came to their senses, and it began to look like a corporate identity

Asus - similar. Sometimes it’s eye-catching, sometimes it’s downright stylish.

pentiumspeed wrote on 2023-10-19, 16:33:

Is this your motherboard in this picture (the blue one)?

I consider all boards with heavy power (those AMD and P4 CPUs) using 2 phase VRM insufficient and I had instability in past. When I moved on to boards with 3 phases or more, I had stability back. 2 phase VRM is also make more noise if you are all about quality of audio. 3 phase and at least 5 to 6 bigger diameter capacitors, not the smaller ones and lot more MLCC capacitors.

Cheers,

On the element base of those times, one phase had a power of approximately 35 watts. For a 100W CPU, two phases is not enough, but I'm not a fan of Brisbane and Windsor. This board running with mobile Turion 😀

Strictly speaking, the current through the capacitors depends on the number of phases. The more there are, the less current.
You can design 1 phase at 100 Watt, but this will not be optimal.

Hoping wrote on 2023-10-19, 17:04:

@shevalier.
It would be interesting to have a calm, detailed explanation, avoiding technicalities as much as possible, about the real importance of ESR and even ESL, and also why a high capacitance is not the most important thing, and the reason why the more expensive the hardware is, more MLCCs and SMD polymer capacitors instead of radial ones you find;

Strictly speaking, the time constant R*C is important for output capacitors. This is the product of capacitance and ESR. The frequency compensation (stability) of the power controller error amplifier depends on this, especially with two-pole compensation. You need to read about this either in textbooks or datasheets with application notes.
There is also a formula for ripple voltage. This is equal to the product of ESR and the change in current. For the same ripple voltage, you need either a smaller ESR or a smaller change in current (more phases).
It’s better to read about this in the application notes
PS. For square voltage, the maximum power of harmonics will be at the third. Those. at a conversion frequency of up to 100 kHz (typical for those years), this will be up to 300 kHz. The capacitance of the MLCC capacitors must be very significant at this frequency. These are not the typical 0.1-1 µF, these should be capacitances of a hundreds µF.
In those years, it was expensive and inaccessible.
Therefore, it is quite pointless, given that polymer capacitors still reach these frequencies.

An example that I know personally is the Fujitsu D3128-b25 that uses many fewer radial capacitors than are usually seen in the VRM, but on the back it has several SMD polymers.

SMD capacitors are placed and soldered at the same time as everything else. Radial capacitors are often placed by hand and soldered in a separate technological process using selective soldering. But it is advisable to glue heavy parts before soldering so that they do not move out of their places.
It's a question of optimizing production, which type of parts is cheaper to use.

From a practical point of view, a general use polymer capacitor is approximately equal to the ultralow ECP electrolyte from 20 years ago.
So the rule of thumb is 0.5~2 the original capacity almost always works well. The appropriate color and diameter, of course.
Otherwise it looks ugly

That seems like a very good explanation, and this thread does seem aimed at explaining how to change capacitors on old motherboards with a point of view from the second decade of the twenty-first century.
So is it possible that in the A7N8X-X in which I use the three 470uf 16v capacitors, these become hot because the VRM only has two phases and is too much current for then because of that? In that case, would putting some SMD polymer capacitors of, for example, 330uf 16v in parallel on the back side improve the situation?

Note, the gold capacitors that Asrock used, for example in the X79 extreme4, also give an interesting appearance on the black PCB.😉
I have one of those motherboards that I bought damaged for €6 in case it had an easy repair, but it turned out to have several deep scratches on the back that cut several tracks.
I don't know how those capacitors would look on a green PCB, I'm thinking of using them for the motherboard of a DELL GX280, which were very famous because they all failed because of the capacitors. I already changed the capacitors years ago with electrolytic ones, but hey, you have to use your free time for something.
I also use a Mobile Athlon 64 3200+ DTR (https://www.cpu-world.com/CPUs/K8/AMD-Mobile% … 3200BEX5AR.html) on my 754 build, it is very good for undervolting and very cold.

Hoping wrote on 2023-10-20, 11:02:

That seems like a very good explanation, and this thread does seem aimed at explaining how to change capacitors on old motherboards with a point of view from the second decade of the twenty-first century.
So is it possible that in the A7N8X-X in which I use the three 470uf 16v capacitors, these become hot because the VRM only has two phases and is too much current for then because of that? In that case, would putting some SMD polymer capacitors of, for example, 330uf 16v in parallel on the back side improve the situation?

The picture shows the VRM of a motherboard supporting FX9370 with a 220W TDP.
Considering that the motherboard has branded polymer capacitors and the conversion frequencies are closer to 100 kHz than 50 (like old motherboards).
Here are only 3 * 270 uF for 220 official watts (And yes, I know that TDP is not equal to consumption)

http://www.nfjapan.com/datasheet/KZG.pdf
super-brended Nippon KZG 470*16 = 1.1Amp * 36mOhm
http://www.lelon.com.tw/upload/prod/169381783974.pdf
unbrended (but known and used) Lelon OCR (polymer general use) - 330*16 = 4.3-5 Amp * 16mOhm
The polymers themselves will be more than enough.

PS. More branded and specialized capacitors will be better.
Well, instead of 20 years 24/7, capacitors will last 50 years.
And the ripples will not be 50 mV but 20.
But this is still better than 5 years and 100 mV for electrolytes.

Hoping wrote on 2023-10-20, 11:02:

I don't know how those capacitors would look on a green PCB,

http://www.samwha.co.kr/electric/product/list_pdf2/FB.pdf
Green labeled capacitor.
I repeat, you should not chase super brands when changing capacitors in a VRM designed for electrolytic capacitors.
These boards have enough mounting spaces for any polymer capacitors to work perfectly. Simply due to quantity.

S775 Workstation Edition - Xeon + FIREPRO V5700 (Radeon HD4670).
You can find what a default motherboard looks like on the Internet.

shevalier wrote on 2023-10-20, 12:48:

PS. More branded and specialized capacitors will be better. Well, instead of 20 years 24/7, capacitors will last 50 years. And t […]
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PS. More branded and specialized capacitors will be better.
Well, instead of 20 years 24/7, capacitors will last 50 years.
And the ripples will not be 50 mV but 20.
But this is still better than 5 years and 100 mV for electrolytes.

There's no empirical data available to suggest that polymers can last 50 years... I have seen good polymer caps degrade when they sat unused for a decade. My NCC "PSA" series caps salvaged from boards are all showing over 20mOhm and their spec should be <10mOhm (tested with a proper LCR meter). Old Fujitsu FP caps (now Nichicon FP) have fared better and all tested within spec.

There's a reason why Panasonic (formerly Sanyo) SEP caps are often triple or more the price than Kemet caps. I would not trust Kemet caps in critical applications. I don't know about other Taiwanese brands (Apaq, Lelon, Capxon, etc...).

Electrolytics OTOH -- there's plenty of evidence to suggest they last longer than 50 years -- especially the ones that have banned chemicals in their electrolyte...

Some Polymers (cough*chinese*cough) can also behave unpredictably... They test perfectly fine, but open it up and the polymer material is crusty and white.

mockingbird wrote on 2023-10-20, 14:37:

unused for a decade. My NCC "PSA" series caps salvaged from boards are all showing over 20mOhm

Khm, its ESR looking like .... "brand new japonise LowESR capacitor"
And what`s the problem?

Hopefully the current KZGs are better than those of the first decade.
As I already mentioned, I almost never buy capacitors, I take them from damaged motherboards and check them on an ESR meter, I am realistic and the hours of use that I give to many things that I repair will not be the cause of failure, in the end I haven't turned on many computers for a long time, months, and some, maybe years. And I'm not going to spend a lot of money on old hardware that is only useful as a hobby or pastime.
But I have never yet found a bad polymer capacitor on a damaged motherboard, even among those used in the first motherboards that had mixed electrolytes and polymers. Even some purple OSCONs from 20 years ago never failed me.
The capacitors on the Asrock X79 board are Nichicon LF series (http://products.nichicon.co.jp/en/pdf/xja042/e-lf.pdf), too good for a 775 motherboard that only supports Pentium 4 I'm going to think about it, I don't have much appreciation for the Pentium 4, however I do like the computer itself, those DELL GX280s were still built like tanks in terms of the case and the exterior of course.
Maybe one day when I'm getting bored... I'll feel like doing it 😀
The electrolytic capacitors that I stopped distrusting years ago are the blue Rubycon ones from the 80s and maybe earlier, Amstrad uses them a lot in their computers and the two CPCs I have are one of the first 464 from 1984 and a 6128 from 1986, and they never failed.
I've even used some of those Rubycons that are more than 30 years old in power supplies from the era of the capacitor plague, and I think it's been longer since I repaired them than it took them to fail the first time.
Also, a few years ago I took out a bunch of electrolytic capacitors, and other things, from two Grundig CRT TVs that were also from the 80s or maybe earlier and I didn't find a single capacitor with a very high ESR value or the capacitance outside the range of the common tolerance of 20% and used then to recap some PSUs, being more than 30 years old they are in better shape than some newer ones.