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MSI PM8M3-V rev. 1 - unstable gaming only

Discussion in 'General Hardware' started by trodas, Aug 27, 2013.

  1. trodas

    trodas

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    I working with computes since 1991 and there is not much that I cannot understand, but this MSI mobo is challenging me. So, the mobo in question is a MSI PM8M3-V with PCB rev. 1.0 and latest bios v1.4 used.

    Board: MSI PM8M3-V (VIA P4M800) PCV rev. 1.0
    Bios: Version 1.4
    VGA: PNY 6800GT 256MB DDR3 350MHz/1GHz
    PSU: Enermax Liberty 620W PSU (replaced caps to quality ones!)
    CPU: 2800MHz Celeron D 336 (133x21) 1.350Vcore
    MEM: 2048MB OCZP4001G 2.5-3-2-7 200MHz 2.60V
    HDD: 500G Western Digital 16MB cache (WD5000AAKB)
    COOLER: Intel box cooler, checked, AS paste applied, cooling good (slowing all the way down to 1000 rpm in reality)
    OC: NONE! (tried FSB 133 -> 138 and it get unstable even in Firefox, lol)
    OS: Windows 2000 SP4 Czech

    More info:
    19" iiyama ProLite E1980SD 1280x1024 75Hz DVI
    DVDRW NEC DV-4551A (16x DVDRW)
    IDE 100MB zip
    floppy with 7+1 USB2 reader Mitsumi FA404
    Using PS2 mouse (Logitech MX510 red)
    OkiPage 14ex laser printer
    NetGear WGR614 fireWall / 54MBi WiFi - OFF

    The Cause
    --------------
    While the mobo is perfectly stable in normal usage, gaming is a problem. At first, I was using there a Radeon 9100 card, yet it can play SoF2 well, so... I working hard to make the mobo stable, it is not stable in 3D games. In the end of making it stable it is not stable even in 2D Windows... lol. Increasing the voltage for AGP = bad idea.

    To cut long story short - at first, it was just a mobo full of known bad caps that sometimes refuse to boot and losing clock AND bios settings when power is cut off. Sometimes it also crash during SoF2 _LOADING_ (never gaming), but that it is. Very rare crash.
    [​IMG]

    So I replaced all the caps, put even these that aren't there back in action and used hi-grade caps. For example the best polymers that even exist Nichicon LE for Vcore and for voltage supply there are Nichicon HZ caps - the best elyte caps even made - king in terms of ripple current, only Samxon GA is "par to par" with them, but that it is. Sourced from Digikey, so, originals.
    [​IMG]

    Result - still not stable. So I blamed the Radeon 9100 with questionable caps and added 120mm fan blowing on it.
    Still no help, rare crashes of game. Fast Writes disabled, AGP 4x (R9100 cannot go faster), 1 WS Write/Read used, Calibration ON.
    So I replaced the Radeon 9100 with GeFroce 6800GT, that have only 3 caps (Chemi-con polymers) and worked well for me before. Truth is a years ago... http://www.techpowerup.com/forums/showthread.php?t=189594

    Problems get worser. Even exiting SoF2 or Quake3 is impossible now. It always freeze on exit...! It get reasonably stable for playing, yet try save screenshot and it crash ASAP. So I try lower the AGP rate (allow me to choose only 8x or 4x), disable Fast Writes, disable AGP Master 1 WS Write/Read and even disable AGP 3.0 Calibration Cycle (one by one). No help.
    So I toyed with the voltage, raising from 1.55 to 1.70 and no help either. (later I find that this is what makes matter even worser)

    Another thing that I added a huge nice heatsink on the NB, because the original one was pretty small and useless. And I discovered beneath it, that there was just a dip of white paste widely off center and that was it. Most of the heatsink did not even have contact with the chip...!
    So I tought - I got this! Laped a BIG heatsink, Arctic past used and screwed it tight on the NB... and again no help.
    [​IMG] [​IMG] [​IMG] [​IMG] [​IMG]

    So the last thing to toy with is the AGP Driving Value. It can be changed from 00 to FF, defaut on Auto show DA.
    Dunno what will happen, but I run out of ideas right now.

    Therefore I'm open to ideas. About the caps - there is one about 10uF SMD cap at the very end of AGP port. This cap I did not replaced. Could this be the culprit? Any suggestion about the Driving Value? I think - try 0 (00), 32 (20), 64 (40), 96(60), 128 (80), 160 (A0), 192 (C0), 224 (E0) and 255 (FF) and see, witch of these values give the best stability?
    [​IMG]
     
    Last edited: Sep 17, 2013
  2. Geofrancis

    Geofrancis

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    have you tried updating the bios?
     
  3. trodas

    trodas

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    I believed that the bios are latest. However that is not true, there:
    http://www.msi-computer.co.jp/support/bios/?p=PM8M3-V
    ...is a v1.5 from 11.12.2006, almost year older that the v1.4 I use. So I started today with the bios v1.5. So I updated the bios, let almost the default settings (all default for AGP) - 8x, Aperture size 128MB, all on, Fast Writes Off.

    However no help. The SoF2 game works well - untill I hit the screenshot button. Then in crash:

    [​IMG]

    So bios are no help and my bios tweaking is not responsible for any failures.
     
  4. zsolt_93

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    One thing i dont see you did is the fact that you reinstalled XP or you reinstalled the game. Just try a clean install of everything, it never hurts for a PC of this age. I have just come back from cleaning out the OS on a Celeron D based XP machine.. and maaan that thing is slow, i never had XP lag on me so hard not even in the P4 days, and this machine wasnt reinstalled for 4 years or so and is used just for websurfing and multimedia, no games whatsoever. A clean OS will elliminate every possibility of software glitching out.
    You could try replacing that one cap too.
     
  5. trodas

    trodas

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    No question that Celeron D is slow as hell, and I will also try reinstall, because I see not much else to do...

    memtest:
    [​IMG]
    Granted. 7 hours of my sleep straight w/o a single error.

    I even replaced all caps on the maninboard (except the small one near AGP port) with the best quality caps ever - polymers Nichicon LE for the Vcore output:
    [​IMG] [​IMG]

    But no help yet.

    [​IMG]

    Prime 95 memory test at the tightest timings the rams can handle - that means CL2!
    (2-3-2-7)
    And I would very much recommend them the stability, because there are damn good caps used for rams now:
    [​IMG]

    Prime 95 CPU test
    [​IMG]
     
    Last edited: Aug 29, 2013
  6. trodas

    trodas

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    HDD tests did not reveal any problem:

    [​IMG]

    ...so I think we can rule HDD or HDD cabled problem out of the question. Also I would noticed HDD errors, and they are nonexistant.



    ...but I suspecting the one cap that I did not replaced yet, because I did not trust caps at all after some failures. I would like to mention that the PC did not started correctly today. After a post it ended in endless loop with just the flicking lene char from dos "_" in the top left corner. Failing to enter the VGA mode once again. Reset fix that, but you know I suspect the cap:

    [​IMG]

    (the small, 10uF 16V (?) one that I did not yet replaced, the rest are replaced with quality Nichicons)

    After two hours of gaming the PC finally crashed (at first, it took two crash attempts to get SoF2 working, but once it is working, then things go smoothly - no more crashes in loading, as with Radeon 9100) and I took the oportunity to diassemble it right away and check temps and then voltages.

    Temps
    CPU Vcore regulators are lightly mildly warm, as if there is nothing going on. Clearly good surprise, they obviously benefit from the quality caps and even under load stays cool. Great.
    GFX card - cold, well cooled.
    But NB chipset cooler (and now it is a BIG one) is relatively warmer that expected. It is not like hot, but clearly I expected lesser temperature. So my idea that a better cooling is necessary might not be far off the reality what is need. That is why I get the Thermalright SI-128 SE... but the damn bottom scews are missing, so I cannot use it :(
    Rams are about the same temp, as the NB heatsink. Well warm, not hot, but warm.

    Voltages
    3.40V, 5.11V and 12.01V on the wires from PSU to HDD/GFX card. Directly on the GFX card connector there is a 11.99V, so the cables and connection give 0.02V drop. Not bad at all.
    Vbattery is 3.56V.
    But what I see as definitive BAD NEWS is the voltage I measured on the last not exchanged cap. And that is precisely 1.55V.
    Ring any bell? Yeees, this is the AGP voltage set in bios! So clearly this cap have something to do with the AGP and it is not at all impossible, that it could be the culprit behind the crashes.

    Because to me it seems that everytime the GFX card should change it's mode of operation (from TXT mode to VGA mode, from 2D to 3D...), then it is very likely to crash.
    Actually todays 4 times it hang on TXT mode to VGA mode switch, during all the resets and powering on and on again...

    Bottom line - dunno if this is caused by the exchange of GFX card or not, but time and bios settings are lost once again, even I put a new battery there.
    (I have to use small GFX card (old good Riva :) ) to be able to measure the voltage on the small SMD cap.
     
    Last edited: Aug 30, 2013
  7. trodas

    trodas

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    Before reinstaled, I installed the NETframework. Version 2.0 works, just install of v2.0 SP1 does not. But in both cases then the testing tools failed miserably:

    [​IMG]

    [​IMG]

    So testing tools that require way too much are out of the question.


    MSI PM8M3-V bois v1.4 (+ unlocked v1.4) and v1.5 (+ unlocked v1.5):
    http://www.mediafire.com/?9npsvnsc8pmzhx1
    http://dfiles.eu/files/z5ar3lnbl
    http://www.uloz.to/xKAgfX51/MSI+PM8M3-V+bioses.zip


    But now I have the C (Win partition) backup w/o any drivers at all (no VIA 4+1, no sound driver and no Forceware driver) and after that installed. And the reinstall really helped. Call of Duty (1), Quake 3 or the cursed SoF2 not crashing on exit anymore!
    Hoooray!

    ...yet still they crash during longer gaming, witch I blame on the cap and overheating of almost everything inside. Mainly the GPU VRM (71°C with just small ATItool cube!) and the NB. The NB I plan to fix using the Thermalright SI-128 SE cooler (just get the missing female screws for P4) and the GPU VRM? Well, I don't know why it overheat that much. But maybe the Chemicon 330uF 16V SMD d10 polymers are not as good as they should be and a replacement of the TWO input caps on the card (the third and last cap on the board is 100uF suxxka) could help?
    Or add another caps for the voltage filtering of the 12V input?
    Or add a serious cooper custom made heatsink on the GPU VRM?
     
  8. zsolt_93

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    Probably they dont require too much (the tools), just the Win2000 is ancient to them. But i see that you are fanatic of that OS so I won't suggest you to move to XP which will surely run the tools and the frameworks needed, not sure if 2000 can run 3 or later. The heating problems shouldn't be on the vrm, those should resist over 100C, the if the gpu temp is high change its cooler, otherwise its no issue, and if you like fiddling with the caps you could change the ones you mentioned if they weren't changed by you before. Seriously this rig should belong in a museum, not in a torture chamber where you throw all kinds of things to it and still expect it to run flawlessly when it was lowend in its time with that chipset and was released well after the OS you use being a socket 775 based PC. Probably mine will run like shit on win 200 too , but its your choice, i only used 2000 (and liked it) on some 1,7GHz P4 Willamettes(that were worse than the PIII and discontinued very fast), but then XP and better P4&their affiliate Celeron chips came.
     
  9. micropage7

    micropage7

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    What about lowering everything
    Lower clock
    I dunno why i feel theres something in your bios that responsible of crashing your system
     
  10. trodas

    trodas

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    zsolt_93 - well, I can check out if I can install some later version of NETframework on W2k, but I dubt that. As being fanatic, well, not quite. I use WinXP, but I did not like them. Dunno why, but I cannot even setup them to show in the open/save dialog the files listed by default as list view ( http://www.techpowerup.com/forums/showthread.php?p=2972060 ) - it always after close and re-open get back to the thumbnails stage, so... I hate WinXP :shadedshu
    Anyway, the windows have nothing to do with the stability, or better put - the lack of it.

    GPU temps are good, just the GPU VRM is very hot. On contrary (quality PSU and caps used to replace the original ones) the temp of CPU VRM are very very low. These heatsinks are hardly warm...!

    Well, not having a better HW now, so I have to manage with this one. And after complete (except the one cursed cap, that might be the culprit) recap I expect the mobo let me play SoF2 at least for several hours, not like for 20 or 30min till crash, lol.

    Old HW run best with old SW ;) Surely I cannot imagine to run Win7 there ;)


    micropage7 - eeew, lower speed? Nah! It is already slow enought! And actually, I just did a overnight Prime95 torture test:

    [​IMG]

    No errors. Claims, that the machine is unstable in terms of CPU are dismissed. It must be the gfx card and/or it's powering.
    And there I did not do any overclock. The 350/1GHz clocks are base clocks and I did not even used coolbites, lol.
    Regardless, the performace seems to get sluggish after few crashes, so it is like the drivers are shutting down to safe mode, witch is very very much slower... The framerate in SoF2 suffers, witch is unexplainable on 6800GT card.

    I also have no idea about the bios, but what could I do to test your ideas? :) It just make me wonder, why Furmark does not work. That will be surely sooner or later make the machine crash... witch it will be proof, that the card is up to the blame - if the last cap not replaced is not at least co-responsible for it... :eek:
     
  11. trodas

    trodas

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  12. Bo$$

    Bo$$ Lab Extraordinaire

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    loving this badass thread. you, sir, are a badass :cool:
     
  13. trodas

    trodas

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    LOL... well, I just have no option but to try harder and fix the problem :eek: I hoped for better cooling, but this is just not materialized yet, as the Thermalright SI-128 SE come w/o the much need backplate nuts for P4 LGA 775 CPU, so... let's get it done.


    Well, the more recent drivers worked and now the card support OpenGL v2.0 and hence - it run FurMark :clap:

    Got a very low score of 547:
    http://www.ozone3d.net/benchmarks/score.php?id=adf68965f6a7ce8c0abbafb8ba784250

    ...but the problem is, that the FurMark did not crashed for about TWO hours straight MaxBurn test...

    [​IMG]

    I was somewhat confused, that the image on screen did not update, but that it probably because FurMark is checking for bugs in the image, right?
    Never the less, I have complain. On screen it write this:
    Renderer: GeForce 6800 GT/PCI/SSE2

    Obviously I have a problem with the "PCI" part, because the card is AGP and given some of the slow-downs it really looks like as it run on PCI speed, not AGP 8x...

    No idea what this cause, but probably some wrong initialization of the card. Regardless if this works as I supposed right, then the card seems to be stable.

    There are minor annoyances too, tough they are not new at all. First at all - opening overlay took for the first time eternity. (1 - 2 minutes) Dunno why that happen, never seen that in my life, but it does happen with different Forceware frivers (61.76 WHQ, 77.72 WHQ) as well, as with different VIA Hyperion 4in1 drivers (v5.24a, v5.11a, v5.04a). So it have to do something with what the card seems to initialize.

    ALSO I cannot get the AGP page back in the drivers. It was there:

    [​IMG]

    ...and now, even I add to the registers the coolbites:

    Code:
    REGEDIT4
    
    [HKEY_LOCAL_MACHINE\SOFTWARE\NVIDIA Corporation\Global\NVTweak]
    "CoolBits"=dword:0000000f
    "NvCplEnableHardwarePage"=dword:00000001
    "NvCplEnableAdditionalInfoPage"=dword:00000001
    "NvCplEnableAGPSettingsPage"=dword:00000001
    It is just not there.
    Also a minor problem is, that the gamma value in nVcpl can be set only between 0.5 and 3.61 - too sensitive, no way to set better value or get back to 1.0 :(

    Kinda bad that FurMark run slow, yet not fail. I did not dare to take a screenshot of the "PCI", but the slow-downs in SoF2 looks like something is wrong with the speed...
     
  14. trodas

    trodas

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    Aaaargh! My card is really running in PCI mode:

    [​IMG]

    ...that is why the speed suxx and also why the nVidia drivers therefore CANNOT show the AGP page, when the card is running in PCI mode...

    Looks to me as simple yet devastating HW issue with the cursed not replaced cap. Now let's source a replacement cap... :(
     
  15. MxPhenom 216

    MxPhenom 216 Corsair Fanboy

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    I would toss that ancient hardware in the trash instead of wasting my time on it. :laugh:
     
  16. trodas

    trodas

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    I would like to to that too - with sledgehammer! :)

    ...however I can't. This is the best computer I have ATM, lol. And besides, I pity the board and want to fix it, so it run hapilly. And since there is only one last cap, then it should not be that hard (after I source a good cap as replacement) to get it fixed.
     
  17. trodas

    trodas

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    Replacement CPU arrived (a HUGE thanks must go to OC AU user Datsun 1600 for creating the missing screws for the Thermalright SI-128 SE and giving me great P4 CPU for neat CPU upgrade! http://forums.overclockers.com.au/showthread.php?t=1097986 ), so I went gaming and... again the PCI/AGP troubles, slow performance, etc. And it crashed during my gaming once again :( Same way as before. Changed box cooler to Thermalright SI-128 SE (greatly temps get reduced) and also now the 120mm fan is blowing to the NB heatsink - yet still no help at all. Crashing. New CPU at least feel much faster now:

    Old MSI PM8M3-V (VIA P4M800) board, new Pentium 4 540 (3.2GHz, 1MB L2) CPU :) Faster a "bit" - 45sec compared to a 72sec with Celeron D suxxka :)

    [​IMG]
    http://valid.canardpc.com/uv65p3

    old: http://postimg.org/image/s85ao8vqv/

    So it is definitively NOT the CPU. The CPU might be dead-slow, yet worked just perfectly. No help in sight, except maybe replacing the last cap with something good, like 10uF elyte change to 47uF tantalum cap?
     
  18. trodas

    trodas

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    [​IMG]

    Now every software claims that the card run in PCI - the damn card must changed the slots by itself, and just forget to tell me about it :D


    After all it more and more looks like a HW issue related to the capacitor AND mosfets around the AGP. Usually when instability happens, increasing voltage fix the problem. In this case, increasing voltages = increasing prblems. The mobo is now fairly stable - that does not mean it is not crashing anymore, it does crashing, but not that much often - (even in light gaming like SoF2, CoD (1) and Quake 2 (KMQuake port with 300MB of hi-res textures) when I use the lowest AGP voltage possible.
    That lead me to believe that the capacitor is the culprit, that overheat the mosfets and they might even need resoldering to the mobo... So next step - obtaining a replacement cap. I think that tantalum 47uF 10V cap ( http://www.digikey.com/product-detail/en/10TPE47MAZB/P16230CT-ND/4146673 ) would be a good and suitable replacement. Plus maybe adding some little heatsink on the little mosfet?

    Should be also noted, that I increased the FSB a lot from 133 to 200Mhz!
    http://valid.canardpc.com/73iuwi
    http://valid.canardpc.com/uv65p3
    And it does not affect the instability of any way. If the problem is the chipset, being unstable for FSB 133, then it would go VERY bad when raising the FSB to 200MHz by using full P4 CPU in the place of Celeron D crap. But it did not happen. Therefore the chipset it cleared from any wrongdoing.

    To show my appreciation I give it a great laped heatsink AND fan blowing at it now:

    [​IMG]

    So there is no more excuses for the crashes that could be attributed to the chipset.
     
  19. trodas

    trodas

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    As for the 10uF d4 SMD cap, I will replace it (shortly, fingers crossed) with a 220uF 4V Tantal-polymer KEMET cap, so that should fix the problem. If it still fail, then the NIKOS poor mosfet is up to the blame and ... what replacement to choose for it??? Anyone?



    Replacement suggestions?

    The AGP regulator seems to be: NIKOS P3055LDG
    http://products.niko-sem.com/images/product/127605182145127.pdf

    This is, in short:
    TO-252 (DPAK) 25V, 50mOhms, 12A, Gate charge 15nC, Gate treshold 1.2V

    ...so, what better with same gate charge/treshold and possibly lower resistance when opened (50mOhms are a bit HIGH IMHO) could anyone suggest?
     
  20. trodas

    trodas

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    Looking at the IPS1011RPbF,
    it have 6V input (max. step down 28) witch is fine (input is 3.3V) but a 10mOhms, should do 18A and the rise time and shutoff time are simply uncomparable with 50uS and 330uS, compared to the 6nS and 20nS :)
    NIKOS owned!

    Sadly, there is gate treshold 1.7V (a bit too high to replace a 1.2V) and also there is absolutely NO WORD about gate charge :(
    http://www.irf.com/product-info/datasheets/data/ips1011.pdf

    That suxx. Something else is probably necessary :(

    Semiconductor NCV8401
    42V, 23mOhms, 33A, rise time 41uS, shutoff time 164uS
    but gate treshold 1.8V :(
    http://www.onsemi.com/pub_link/Collateral/NCV8401-D.PDF

    Infineon BTS 3142D
    42V, 28mOhms, 30A, rise time 60uS, shutoff time 60uS
    but gate treshold 1.7V :(
    http://www.infineon.com/dgdl/BTS3142_DS_13.pdf

    ST Micro
    40V, 35mOhms, 12A, rise time 350nS, shutoff time 450nS
    gate treshold (forward on voltage) should be 0.8V, witch is pretty good
    gate charge is not listed there, but todal is 36.8nC
    http://www.st.com/web/en/resource/technical/document/datasheet/CD00002219.pdf

    ...that one could be it...?
     
  21. natr0n

    natr0n

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    Maybe a fresh OS install will help or possibly update DX?

    also,try 3-3-3-8 for memory timings.

    You do some nice cap replacing btw.
     
    Last edited: Nov 8, 2013
  22. trodas

    trodas

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    Oh, thank you. And Win reinstall? Sure this should be tried, but not before the computer can hang on just after the post. That is not the time to fiddle with Win, because they did not cause this.

    Also rams are fine, used to run far faster in different mobo, no crash related to ram or CPU - EVER - occured there. So I will concentrate on the HW issue.


    From this very interesting link:
    Vishay - MOSFETs - N-channel - DPAK (TO-252) package
    ...I choose this one:

    Vishay SUD50N02-06P
    http://www.vishay.com/docs/71931/sud50n02.pdf
    20V, 6mOhms, 26A, rise time 10nS, shutoff time 24nS
    gate treshold 0.8V, gate charge 19nC

    Even that at 4.5V the resistance is actually 9.5mOhms, then it is still far better that 50mOhms.
    Also the mosfet can operate at 175°C, witch is pretty high.
    While it is a bit slower (rise time 10 to 6, shut off time 24 do 20), the gate treshold 0.8V should compensate that a bit for the original is 1.2V... The slightly higher gate charge 19nC over 15nC should not be a problem.

    I believe I found the perfect replacement, that is better than the original!


    I managed to replace the last remaining capacitor on the MSI PM8M3-V mobo - the 10uF d4 SMD suxxka, that have kinda horrible ESR or 3.2 Ohms:

    [​IMG]

    ...with a new SMD tantal-polymer KEMET 220uF 2.5V capacitor T520B227M2R5ATE015
    [​IMG]
    ...with have ESR around 0.015 Ohms :D

    That should be a huge improve. Also I, out of the desperation, resoldered a bit the drain tops of there NIKOS mosfets near the AGP slot.

    And result?

    ABSOLUTELY NONE!

    So it looks like that the mainboard was not up to the blame the whole damn time. It is the videocard that have to be recapped.


    The Radeon R9100 was crashing when new SoF2 level is loading. Given that it run passively cooled on Licon caps:

    [​IMG]

    ...with 60 mOhms ESR one should not wonder. Rest of the caps looks quite similar, so recapping is in order, just waiting for the caps (as usual).


    The PNY 6800 GT failed after a short time to run in AGP mode, going down to PCI mode and crashing after some gaming is played. Now that is serious problem, because there are just THERE caps, two of them polymers on the voltage input filter and they are Chemicon polymers.
    Last one is unknown 100uF SMD cap and that it is for other that ceramic caps! I would be inclined to add some caps in the blank spots too, probably something over 100uF SMD... and I would also like to create a custom effecient heatsink for the mosfets on the card, because they do overheat a lot - GPU VRM temp 71°C: View image: temperatures after 30min


    Should I try recap these graphic cards before I try replacing the NIKOS mosfets? :confused:
     
  23. EarthDog

    EarthDog

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    Why, with you, on every forum I have seen you in, does it always come down to caps? :p
     
  24. trodas

    trodas

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    Dunno.
    Maybe because they are always faulty by design...? Or I have a bad luck? I have no idea, but on the Radeon R9100 are bunch of pretty bad caps for a loooong time, so it makes a perfect sense that it does not work stable or reliable... witch forced me to dig out the 6800GT (witch is also much faster - not when run in PCI mode, tough) and if the Chemicon polymers are bad on the 6800GT, then it again boil down to caps in both of these graphic cards that I can test there.

    Yesterday I worked on the R9100 and except two last remaining crap caps I replaced all with quality Nichicon polymers (with bumped capacitance and uncomparable ESR) and even added two polymer caps where they are left (still 10 places on the mainboard top are left empty and one for SMD ceramic at bottom of the card are omited) and added 4 pcs of ceramic SMD caps where they are omited at voltage filtering for each set of two ram chips (8 chips, both sides used).

    Now the card is starting to look kick-a$$ and very nicely, thx to these great looking polymers!

    So with some luck and help of friend(s), I should be having next week the remaining caps for the Radeon R9100 and then I do "upgrade" and we see, if it will work reliably now (eg. no crashing on level loading in SoF2, AGP 4x speed (absolutely kick-a$$ upgrade from the PCI speed!) and noproblemo when opening overlay for videoplayback).

    And if I'm right and it will work reliably now, then it is absolutely clear, that the 6800GT have faulty caps - even they are Chemicon polymers, that are somewhat mostly considered as good caps...

    Sidenote - it will be interesting, if and how much the R9100 can be overclocked with this caps upgrade :) I also already gathered the caps that are omited on the MSI PM8M3-V into the CPU socket (from 10 ceramics, only 4 are there and the big tantal I will replace for a new tantal-polymer POSPAP cap with huch higher capacity and almost uncomparably lower ESR, yea!) ...

    Sadly I have to wait with this upgrades for the GFX card test to be absolutely sure that I can blame the Chemicon polymers on the PNY 6800GT and nothing else.
     
  25. trodas

    trodas

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    Quick report - after recapping the Radeon R9100, I put it into my MSI PM8M3-V mobo and at first it show ram errors (heartbreaking, after so much work and so many polymers and added caps...) on the screen, so I have to pull it off and check.
    Fortunately, I managed to find the bit of tin, that ended up on one of the bottom ram chips and after cleaning - hoooray, all works like a charm!

    Immediatelly the card go into AGP 4x mode (!) and despite being TAD slower that PNY 6800GT, the system feels notably faster. That is, because, PCI mode DO SUXX BADLY. Therefore it is getting almost sure that the mainboard was NOT for the blame. The bad caps are in the GFX card(s), witch I indent to fix, of course.

    Now is time for a clean win install and then I do more testing - mainly the play testing and longetivity under serious load. Then I might be inclined to see, if I can overclock the card a bit, despite the poor speed to start with :)

    The lesson from all this is too early to draw, but there are only 3 caps on the PNY 6800GT, that are not ceramic: two Chemicon polymers 330uF 16V d10 SMD and one 100uF 16V d6.3 SMD Nichicon UD with 3.4V on it + some empty spaces, but that it is.

    Since I was getting about 71°C on the VRM mosfets ( http://postimg.org/image/x9m8pl4sl/ ) with just the ATI tool cube in small window, then I suspect these Chemicon polymer caps are up to the blame.

    Of course the cooling of these mosfets is poor, but that was unchanged since day one and the card worked well for me before, so...
     

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