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In Reply to: RE: How to Power the Memory - Linear Regulator posted by Mihaylov on November 22, 2011 at 11:12:28
Hi Serge and fellow members of this forum,When we start to tamper with the PWM circuit on the MB, we begin to scratch its heart and soul. We are fully aware of the improvement brought about by implementation of full linear PS in place of the switching PS in ATX format.
Would a linear power supply for memory give a SQ enhancement, even if a full linear PSU for P24 and P4 is used? Perhaps I should rephrase the question in technical terms: "Would replacement of the on-board single phase switching power supply by a linear power supply enhance SQ?" I would say most definitely. Our full linear PS implementation has proven this. Nevertheless, improvement in SQ will largely depend on the quality of the linear power supply used. My experience is that whilst powering the MB with SLA batteries + 3-terminal reg., I then powered the memory with batteries resulting in good SQ improvement. Replaced by a LT1083 also improved SQ but not to the extent of battery. When powering the 5V rail with batteries I was in heaven. As Greg said, "Everything matters!" All minor improvement work add up. Don't know how it will sound when powering both 5V rail and memory by batteries at the same time.
With regard to implementation of memory power supply on H55/H61 series MB, as well as others, I have the following options in mind, in order of superiority:1. NiMh battery (suitable for H61 MB)
2. Shunt regulator buffered by NiMh battery (suitable for H55/57/61/67 MB)
3. Shunt regulator alone (suitable for all MB)
4. Series regulator made of discrete components (suitable for all MB)
5. 3 terminal series regulator (suitable for all MB)
6. Onboard switching regulator buffered by NiMh battery (suitable for H55/57/61/67 MB)So far, I have tried options 1, 5 and 6 on MBs. I have also tried 2, 3, 4 and 5 on other audio circuits. Hence I can tell the difference.
Application of the above options will largely depend on how desperate you wish to improve SQ, the ease of construction and MB model/electrical characteristics.For H61 series MB, memory can run as low as 1.1V. Therefore, I will definitely go for NiMh battery(1.25V). However, there are some variations, e.g. whether to use 2-3 D size Nimh batteries or 1 Nimh battery backup by a large LifePo battery (2 more variations here in terms of backup battery connection - whether to use resistor or shunt regulator for voltage drop, the latter would be a combination of option 1 & 2 and may be a balanced approach in terms of maintaining purity of power supply and stability of voltage).
For H55M-UD2H, pure battery is not feasible, as memory won't work below 1.3V or so. Therefore, other options should be used. For G31 MB, the DDR2 memory runs at 1.8V and is therefore not suitable for battery operation.
It will be a long story. Hence, I will divide my writing into parts and start with the easiest options.
Option 6 - NiMh battery buffer for H55/57/61/67 MB
You only need a relay e.g. 12V, a diode, four wires and a C or D size Nimh battery in a holder with connecting terminals.
(a) No need to remove the choke powering memory
(b) Fix the battery/holder and relay somewhere on the MB near to the memory using double side adhesive tap.
(c)Connect the coil of relay to 12V and ground of P24 on MB, a diode 1N4001-4007 or similar in parallel to the coil(cathode towards P24 12V).
(d) Connect the negative of battery holder to P24 ground of MB.
(e) Connect positive of battery holder to the moving arm (COM) of the relay.
(f) Connect NO pin of relay to the output point of the choke
Upon MB startup, the battery will be connected, by the relay, in parallel to the on-board memory power supply. It is simple work which can be done in half an hour. The modification is safe, will improve SQ but won't hurt the MB, just be cautious about polarity. In addition, Ram voltage should not be set to 1.45V or above, use the lowest voltage possible to run the ram. The battery acts like a capacitor under this config. and I found this buffer better sounding than bypass caps. Of course, quality caps should also be added.
Option 1 - NiMh batteries for H61/67 MB
The connection is similar to option 6 above but the choke should be removed. More batteries connected in parallel are needed for longer playing time.
A stock battery charger can be put/stick inside the case. Negative terminal of charger to Gnd of MB, Positive connected to the NC pin of relay. When MB is power off, it will charge the batteries provided that it is always connected to the AC mains.
Option 5 - 3 Terminal Linear Regulator for all MBI'll take some photos to illustrate the construction. Please feel free to ask any question. See you in part 2.
Edits: 11/23/11 11/23/11Follow Ups:
How to make a 3-Terminal Regulator for H55M-UD21. Remove the choke as per photo.
2. Cut a small piece of PCB that will fill the gap.
3. File with a filing tool to ensure good fitting.
4. Prepare two resistors with strong leads that will pass through the two holes of the choke. One of the leads is for support purpose and there is no actual connection to the circuit.
5. Put the heatsink on the PCB to mark position. Do not put it too close to the P24 socket.
6. Drill holes for LT1083 and chokes
7. Place component on PCB. (I forgot to put resistor to adjust the regulator to 1.3V). Anyway, you will see the placement of components and connections more clearly in the next part.
8. Soldering. The resistor lead near the middle of the PCB is only soldered to the Mobo to provide support. There is no connection to the circuit in the PCB.
9. Connect In to 3.3V and Ground to P24.
Please see Part 2.2 for the circuit diagram. In part 2.2, an external supply will be built.
Edits: 11/26/11
None of your pictures came through on my pc. Hope its not a problem on my side.
Rectified.
Thanks Jack...looks fine now. Remember I have the G31-E2sl mobo. I remember a aseries of posts between you and Gene wherein you helped Gene do this but I had a difficult time following Gene's pictures/markups...didn't appear clear on my pc. But after I figure out what I have to do ... I would like to do this mod.
.
In Part 2.1, I built a regulator board attached to H55M-UD2H to power the memory, but I never listened to it singing because I used batteries.In this Part, an external regulator board is built for general use with all Mobos. A GA-G31M-ES2C Mobo is used for the test. For your interest about the listening test, it is at the bottom of this page and I recommend you read about the results first.
Construction
1. Prepare components, mark position/holes with a pencil and dill holes.
2. Circuit diagram and components layout
0.1uf cap should be added to all caps. You can also add the cap that I crossed out for even better filtering effects.
3. Remove the choke from the Mobo. May need to use solder iron to press out the choke from the solder side.
4. Connect wires from P24 3.3V and Ground, as well as from the choke output.
5. To power the DDR2 ram, tune the VR to maximum resistance, i.e. 50 ohm combined.
6. Connect the wire to the regulator board. If you're not sure whether the regulator will work, connect it to a power source e.g. a 6V battery or other power supply and check the output.
Listening test.SSD powered by batteries, Antec Earthwatt 430, battery powering USB isolator and stock Musiland 01USD, battery driven AD1865 DAC, 45-tube power amp. CPU running at 960Mhz, forgot what CPU was used, must be a low-end one. Bios optimized.
The Mobo with DDR2 Ram booted up when the regulator was about 1.53V, with power taken from P24 3.3V. I miscalculated the resistor values(this set of resistors, i.e. 200/50 ohm, will output 1.53V not 1.8V), but never mind, it booted without problem.Few day ago, I listened to this Mobo while doing some tests and I wasn't pleased with its SQ at all. Last time I assessed some Mobos, I graded this Mobo slighting above my Atom Mobo and the H55-UD2H was much better sounding.
With the implementation of linear regulator for memory, it sounded so much better than I could image, it is way out of expectation. Running the ram at lower voltage (1.5V) has some bearing on SQ(standard is 1.8V).
I further reduced the voltage to 1.3V whilst CMP was running. Power off
and then power on again. It booted up without problem at 1.3V. Current was about 2.3A.
At 1.3V, I was getting better music. Some noticeable improvement, minor details was clearer and background noise was lower. Under this set up with standard switching PS, no separate P24 12V and stock USB converter, I would rate the Mobo (modified with bypass caps) sounding very close to stock H55M-UD2H or perhaps better in some aspects.
I strongly recommend building a linear regulator for the memory of your Mobos. Theob, you should try. It is not complicated at all but it really makes a difference and you will be paid off. I believe the memory power circuit is more important than the rest in the mobo e.g. CPU core and graphic, it is because wave files are loaded to the memory for playing and it is the source of what we will be hearing. Therefore, a noise free environment is paramount.
Boards like H67M-UD2H-B3 also has a single phase switching power circuit, albeit using low RDS(on) Mosfet, hence will sound better. Nevertheless, it is still a switching regulator with that particular sound signature. The 2 chokes before and after the regulator help filter out much of the switching noise and listening was enjoyable, even when no linear regulator was used in the front end. Powering the regulator by P24 3.3V is convenient but not mandatory.
In Part 3, I will skip Option 4-"Series regulator made of discrete components" as I never have liked it. Instead, I'll go to Option 3 to build a sub-voltage shunt regulator(my favour), to power the memory. The design goal is an adjustable shunt regulator capable of delivering voltage as low as 0.6V to 1.3V and with more than 2A of current delivery capability. I've sourced the necessary components and is waiting for its arrival.
Edits: 11/26/11 11/26/11 11/26/11 11/26/11
Jack a quick question. If I'm running my memory on battery power and the battery runs too low will I crash my cmp pc or will it simply shut off? This is a big operational factor.
Not an issue at all. I can't recall, those were either BSOD or totally black screens, BSOD most probably. But not a single problem rebooting.You shouldn't worry about it and experience the battery memory sound. 3.3.V 10AH will last 1 hours, probably. If you like it, there are many ways to extend battery life.
I should remind you to use a 1GB Ram for the first test, as I have not measured the current of smaller RAMs. Try my setting first. If your mobo will not boot with the given setting, the memory is drawing large surge current at start up, thereby causing excessive voltage drop across the resistor.
Should this happen, you should decrease the 0.75Ohm resistor to 0.72 or 0.68.
Should this fail too, you will need to add a fully charged 1.25V NiMh battery(at least 5AH). So, LifePo> resistor> NiMh> RAM, but powering on is a bit tricky because the 2 batteries should only be connected through the resistor when powered on.
This is a simple but rewarding experiment that can be worked out easily.
Edits: 12/23/11 12/23/11 12/23/11
Ok Jack I just may take a crack at this. I'm thinking of taking a 3.3v feed from a 2nd antec I use to run my cpu. I assume there would not be a problem with ground loops but prefer to hear your opinion on this. Also would wire length from circuit to the G31 mobo be critical? I have run out of realestate in my pc. Also to remove the g31 choke should I also use a heat gun?I have a couple of spare mobo's and another cpu so this would be a nice project wherein I can take my time do it right and have my current mobo/cpu as a backup.
One thing regarding the heat sink do I need one that big or is that just a piece you had handy?
Also what size chokes in terms of millhenries and power? What wattage on resistors? I take it that in to the regulator is lead from left of 2RO in your picture and out to the board is the the lead (or hole) on the right of 2RO? If you are booting at lower than 1.8v (1.3-1.5v) does this make a battery feasible?
Edits: 12/08/11 12/10/11
Hi Theob,For heatsink, the one I used in Part 2.1 is the minumum requirement. The regulator will disspate more than 4W of heat. You could use one third the size of heatsink that I used in Part 2.2.
Use an iron solder to remove the choke. Heat up the soldering point and press down the pins one after another. No need to find a choke, use the one that you will desolder from the mobo. Put one choke on the output of the reg. If you have more chokes, put another on the input side of reg.
1/2 or 1/4w resisitors wil do.
No problem with ground loop if you use a seperate PS. Don't worry about the wire length, it will work. It's not a permenant setup afterall.
"I take it that in to the regulator is lead from left of 2RO in your picture and out to the board is the the lead (or hole) on the right of 2RO"
That's not correct.r
Only the hole close to the ram slot will be used. The output terminal of the Reg. goes to this hole, with a choke in between.
The input to the reg. and 0V shouild be taken from the P24 connector. 3.3V (input to reg) and 0V both taken benneath the P24 socket. Plug in the P24 and you will see the colour of wires. The 3.3V is organge and 0V is black. One set of these wires just happen to be located on the edge of the socket near the choke, connect (solder) benneath the organge wire. This wire will be connected to the input of reg.(if you have more chokes, put one in between) Do the same for the 0V black wire which will connect to the Ground of the reg.
A new idea
I am going to power the RAM by using 3.3V Lifepo battery. Since you have the same, so you may want try this before I do. It should work better than NiMh batteries.You need:
a 3.3V => 10AH battery(small ones parellel them), 10W 0.75 ohm and 10W 0.82 ohm resistors, 16V 4700uf cap.
Simplily connect + of battery to one end of 0.75ohm, the other end of the 0.75ohm to the hole nearest to the RAM slot. Connect - of battery to any ground of mobo(black wire). You may need a switch for start up or may twist the wires for connection. You also need to solder a 4700uf Cap, - to Ov of Mobo, + to the only hole on the mobo, i.e. the 0.75ohm R and + of cap go to this hole, and - to the ground.
Make connection and measure the voltage on the other end of the 0.75V R, which should be around 1.5V, then power up the mobo.
And then enjoy music and the improvements which will be more significant than any of the tweaks you've tried or even their accummlated effects.
You may change to 0.82ohm to see if it will boot at lower volatge.
Edits: 12/14/11
Using a bunch of 3.3 lifepo4 batteries is a great idea and simple to implement! What is purpose of twisting the wires?
Edits: 12/14/11 12/14/11
Thanks Jack .. just what I needed. I will order the parts now.
For temporary connection without soldering - joint the ends of two wires together by twisting them. In this case, one wire from the choke hole and the other from the 0.75 ohm resistor.
Let me know the good news! I haven't tried LIFEPO yet.
Further to my tests with 1.3V, the DDR2 800 1G Ram will boot up at 1.25V. The sound is mellow at this voltage and the Mobo sound like a tube amp.I also tested the regulator board on the H61 Mobo and there was good improvement, but not as drastic as the G31 Mobo. The stock H61 Mobo sounded thinner than the G31 but is more analytical. After the regulator is used, H61 Mobo sounded thicker and more balanced.
Edits: 11/27/11
This is very very interesting and useful. Continue please.
Serge.
http://cmp2-mihaylov.narod.ru/
My cMP2: Windows XP SP2 Ru, Gigabyte GA-H55M-UD2H, Intel Core i3-530, Corsair CM3X160C9DHX 1GB, system drive - Transcend IDE FLASH MODULE TS2GDOM40V-S, ESI Juli@, full linear PSU, NAS - WD My Book Liv
Thanks Jack for the detailed answer. It is very interesting. We wait for continuation.
Serge.
http://cmp2-mihaylov.narod.ru/
My cMP2: Windows XP SP2 Ru, Gigabyte GA-H55M-UD2H, Intel Core i3-530, Corsair CM3X160C9DHX 1GB, system drive - Transcend IDE FLASH MODULE TS2GDOM40V-S, ESI Juli@, full linear PSU, NAS - WD My Book Liv
I never worked with relays so I am unfamiliar with them. I assume you get a 12 v relay is that correct? What current capacity? Is it obvious what terminals are NO, COM and NC? Where is coil output? What value of voltage should batteries be? Is it critical? I think the onboard voltage regulator is still operating so battery voltage is not too critical, correct? How do you remove the choke cut or desolder? Which component is the choke on G31-e2sl?
Hi Theob,
Unfortunately G31-es2l uses DDR2 ram which runs at about 1.8V, at present no battery can deliver such voltage. To enjoy listening to battery-powered memory, you will have to wait until you change to H61/67 chipset MB or newer 22nm CPU next year. My apology for my unclear presentation. I've made relevant amendment.
In your case, a 3-terminal linear regulator set to about 1.8V is the way to go. I've built an attachment board with 3-terminal regulator on H55-UD2H. I also have a G31 MB and will built a general board for use in all MB including yours. Will present tomorrow.
Thanks Jack...take your time I appreciate it.
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