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DeWitt

Please help clear up inconsistent info on PWM IC's (function, temps, l

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[( Please correct me where I'm mistaken or missing information! New info will be updated as it comes in. )]

 

*Updated 1/18 1pm! Thanks to soundx98 @ DFI-Street*

 

I'm hoping to find out (from somebody who REALLY knows what they're talking about) some accurate info on PWM IC's. I've done some searching and here's what I've found (reference board below)...

 

What is it? - Pulse Width Modulation Integrated Circuit

It actually consists of three parts

1. PWMIC - rectangular chip below VDimm MOSFET and to left of ATX Connector

2. The three MOSFETS with Heatsinks soldered to them

3. The sensor - to right of CPU and left of sinked MOSFETs

 

 

What does it do? - It controls/adjusts/filters voltages from PSU to supply the board components.

 

Where is it? - The circuit includes (1) the rectangular chip below VDimm MOSFET and to left of ATX Connector and (2) the three MOSFETS w/ HS's soldered to them. The sensor ids the small yellow "thingy" between the CPU and sinked MOSFETS.

 

What are some recommended temps? - __^C idle and 45-55^C at full load.

 

How do you lower the PWM IC temp? - I've only found two solutions for this: (1) Arctic Alumina or chromatics "tape" and heatsinks or (2) instal a small fan directed at it (most popular). This appears to be irrelevant unless your experiancing instability during high temps.

 

Reference board - LanParty nF4 Ultra-D

 

 

LanParty.jpg

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The sensor is circled in green. It is definately affected by air flow and heat generated in the area. The actual PWMIC is the black rectangular chip below the Vdimm MOSFET . The three Huge Heatsings are soldered on to the MOSFETS that supply the board.

 

So why would the sensor be so far from the actual PWM IC? The location would lead one to believe it's monitoring the MOSFET temp, right?

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From DeWitt's edited 1st post in thread.

 

What is it? - Pulse Width Modulation Integrated Circuit

Actually consists of three parts

1. PWMIC - rectangular chip below VDimm MOSFET and to left of ATX Connector

2. The three MOSFETS with Heatsinks soldered to them

3. The sensor - to right of CPU and left of sinked MOSFETs

 

What does it do? - It controls the voltage to the CPU.

The circuit controls/adjusts/filters voltages from PSU to supply the board components

 

Where is it? - Most people seem to say it's one of two things: (1) the mossfets between the CPU & IDE slots (not sure if they're referring to the round ones, square ones, or one's with HS's already on them) or (2) the black rectangular chip to the right of the DIMM slots just above the square 4-pin connector.

See post above for clarity the round deals are capacitors

 

What are the proper temps? - __^C idle and __^C at full load. I can't seem to find a straight answer on this. All I've found is that they've been known to operate as high as 100^C, although this is not recommended. I've found that idleing at 50^C is a bit high and that your system will probably lose stability before any damage occurs b/c of high PWM IC temps.

Typically between 45 degrees and 55 degrees under load. Lot will depend on case air flow, size of fan and overlap on heatsink, size of case, heat generated by CPU. I don't think a blanket statement that over 50 degrees will cause instability is valid at all. I've had two rigs prime succesful overclocks at 55-57 (with extra fans removed) without issue. Again a lot of variables here.

 

How do you lower the PWM IC temp? - I've only found two solutions for this: (1) thermal paste and RAMsinks or (2) install a small fan directed at it (most popular).

I think most use a fan of some type because it can often be a "deadspot" since it's blocked often by HDDs, cables. etc. If you read on in Post #2 in the MBM thread there are some great thermal pics from BigBruin as well as "hotspots" that could have additional heatsinks added. Thermal paste won't cut it, but Arctic Alumina or some chromatics "tape" may secure them properly. I haven't experienced any increase in clocks by using additional heatsinks but it may be the way to go if fan noise is objectionable to you.

 

Again, I'm not an engineer or an IT guy. Just trying to help here. So feel free to post comments or questions. I'm gonna paste this into the MBM5 thread if it makes sense to folks.

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Original post updated - Keep the info coming!

 

Temps would be nice. Anyone ever get instability due to high temps? What are the highest temps you've seen it at (stable or not)?

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Original post updated - Keep the info coming!

 

Temps would be nice. Anyone ever get instability due to high temps? What are the highest temps you've seen it at (stable or not)?

 

 

BF2 went apeshit (that's a technical term for my framerate going from 70's to suddenly dropping in the 10's) when I played it for a while, and when checking temps the CPU and GPU were fine, but the PWM was approaching 60 :(. Not sure if they're related directly, but it's something that concerned me enough to buy a fan for the area.

 

Speaking of FANS, does anyone have any photos of example fan placement location in their case? I have an 80mm that I'm going to put in there, and I know that might be too big, but I was wondering if you guys had any ideas of some placement- I was going to zip tie it between two pre-ziptied ropes of cable. Might look ghetto, but I don't have a windowed case ;)

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