MSI K7T266 Pro (Ver. 1.0)

[ssl6]

Hey Everyone,

Long time lurker, but I think this is my first time posting.

Just looking for some assistance on identifying some suitable replacement capacitors for an MSI K7T266 Pro (Ver. 1.0). I just got my hands on two of them actually, both working but one has some visibly bulging capacitors and the other has a few that I can't tell for sure if they're bulging because it's faint at best if they are.

I'll be honest I don't fully understand much on capacitor spec sheets beyond voltage and capacitance but I can solder like nobodies business so I've done lots of recapping but typically have been able to find suitable replacements in existing posts here where someone has already posted a list of part numbers. In the case of these most of the posts for this specific v1.0 board I've found are old and just went to RMA because at the time manufacturers were replacing boards due to the plague

Anyhow, may as well start with an inventory of all capacitors on these boards and list what I have on hand that might be a good replacement if anyone can help confirm?

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5x 12mm diameter 6.3v 4700uF KZE (chemi-con caps I think?) - none of these appear bulging so not sure I should change them unless they're known to have some issue over time

I have available already, but only 3300uF
nichicon hm(m) 6.3v 3300uF
nichicon hd(m) 6.3v 3300uF

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9x - 8mm diameter 6.3v 1000uF chhsi/tayeh - these are the ones that are bulging on one of the boards. one board has chhsi caps, the other has tayeh. I know these are some of the known no-name caps that were problematic and definitely should be replaced, just need a replacement part #

I have some chemi-con KY caps matching this voltage and capacitance in my stock. Also some Rubicon YXS


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5x 10mm diameter 6.3v 1500uF tayeh caps - these appear to be okay, but probably should be replaced I assume simply because tayeh, so just need to identify a replacement part #



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3x 6mm diameter 10v 470uF chhsi - probably should replace but need part #



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4x Sanyo OS-CON 510 / 4 - these appear fine. found another thread on here that suggested these as a replacement though
https://www.digikey.ca/en/products/d...PC560M/4204187



I thought I had more options in stock for some, but seems regardless I'll need to order from digikey or elsewhere if I'm to replace everything. Any hlp appreciated. I'm also not opposed to polymodding it, although some may argue it's not worth the cost but I like tinkering and I've been on a retro hardware binge and having fun with some of the stuff I've had hoarded away for years and will probably keep for many more years

[stj]

Re: MSI K7T266 Pro (Ver. 1.0)

add pictures so we can see what the caps are doing

[DynaxSC]

Re: MSI K7T266 Pro (Ver. 1.0)

The electrolythic caps are not very critical components, usually you can just exchange them to different vendor. Look for good quality components (Nichicon/Panasonic/Chemicon are very good) and matching size/case, capacity, max. working temperature (the higher the better, the caps usually have the max. working temperature printed on the case) and internal resistance of the caps -> ESR (the lower, the better). If the caps are several in parallel, better exchange them all, if they would be different make. The one with 4700uF just try with 3300 uF and look if it works. Also a good method to source the caps is to buy a cheap broken but newer msi board with similar or same make caps and transpalant them. Another question is if it is necessary to exchange them at all, usually caps work 10 years and longer (dependent on working time and environment conditions/temperature/load), if they are not swallen or physically damaged they might still be OK. You can just take out and check a few samples or all with a meter able to measure capacity and ESR, and if they are still OK, just leave it, but, excluding the "no name" caps - it is definitely good to exchange them. Remember heating the caps is not very healthy for the caps, so do it as seldom and fast as possible. Also pay attention when exchanging them, this board is quite old, and the board quality in that times was not so good as today, the tracks/pads/baord material are much more sensitive to heat/mechanical solder iron pressure under heat, then todays boards, it is quite easy to damage them. You definitely need to use in parallel a preheater, hot-air and a solder iron to do it safely. Place the board upside down over the preheater (set preheater to no more than 150C-170C, give some 5cm distance, protect the plastic parts with captan tape at least 2 layers or demount them if possible), use hot-air to support the heating (350-400C, 5 cm) and solder iron from the other side. The caps should fall out due to gravity once tin is fluid.

[ssl6]

Re: MSI K7T266 Pro (Ver. 1.0)

Here's some pictures of the board. You can see a few of the smaller no name 6.3v 1000uF caps are bulgy. but the slightly larger 1500uf caps are no names as well and they currently look okay, but I'd like to change them.

The large chemi-con kze 4700uF caps all look okay on both boards and unless someone tells me there's an issue with those from that era I'm not really inclined to replace them

As stated, I have some Rubicon YXS series 6.3v 1000uF caps I can use for the small guys where a few are bulging. enough to replace all on both boards and then some. I don't have anything to measure esr or anything off existing caps which is why I'm hoping someone more knowledgeable can verify. But even if i had something to measure them

[stj]

Re: MSI K7T266 Pro (Ver. 1.0)

the critical caps are the oscon polymers and the large caps near the ram.

the polymers if you change them should remain polymer - maybe kemet or panasonic if your on a budget.
the other caps - i would either use panasonic FR or polymers - whichever is cheaper

you dont say what country your in,
for whatever reason panasonic are the cheapest caps in europe but nichicon and other japanese stuff is cheaper in the u.s.

[ssl6]

Re: MSI K7T266 Pro (Ver. 1.0)

okay, so for critical caps, the OS-CONs are the Sanyo caps. they look fine visually so I don't think there's any need to replace them

as for the other larger caps near the ram, those tayeh/no name 6.3v 1500uF caps. These are some I definitely want to replace as they're well known to be bad from my knowledge. I can order order these as a replacement for them

https://www.digikey.ca/en/products/d...MDO1TD/4991300

Unless I go polymer, not sure what would be recommended? from my understanding, if I go polymer the general rule of thumb is to cut capacitance in half? I have 5 of these on hand currently, 10v though, not 6.3v, but maybe I could use these?

https://www.digikey.ca/en/products/d...J152LB/2504173

[momaka]

Re: MSI K7T266 Pro (Ver. 1.0)

The Chemicon KZE caps can stay - these are pretty good stable series.
The Sanyo OSCON caps are polymers and likely will never have any issues for the lifetime of the board's use.
Tayeh and Chhsi need to go for sure.

By the looks of it from the pictures of this board, two of the KZE filter the 5V rail for the CPU VRM, while the other three KZE and the Sanyo OSCON filter the CPU V_core. Everything else appears to use linear regulators on the board, so no need to care too much about ESR.

The Chemicon KY caps you have should be fine to use for the 10V 1000 uF caps, provided height is not an issue, as KY is a little taller. If height is an issue, Rubycon ZLQ 6.3V 1200 or ZLH 6.3V 820 uF will work fine too - at least these tend to be the cheaper low-ESR caps right now in USA (and maybe whole North America.) I use these a lot of all sorts of motherboards. Panasonic FR, FM, and FS are good too. Since ESR is not too important for this particular board when it comes to the 10V 1000 uF and 1500 uF caps, even Nichicon HE will be fine.

On that note, Nichicon HD is also fine (it has slightly better ESR and RC than HE... though I find HE to be more reliable in high-heat areas.)

Finally, you mentioned you have Nichicon HM caps in stock. Before you use these anywhere, make sure their date code starts with H06 or higher. H05, I'd say is marginal (usually OK for the 16V and higher voltage parts, but might not be for the 6.3V and 10V parts.) H01-H04 should be avoided from the HM & HN series - these are known to have problems. Another one to avoid is Sanyo WF series.

*EDIT*
The Nichicon PLG 10V 820 uF caps from the first link (PLG1A821MDO1TD) will likely be OK to use for both the 1000 uF and 1500 uF caps... but at over $2.50 a cap, I don't see a reason to go with these, especially considering the board uses linear regulators throughout (except the CPU VRM) so it won't care. In fact, linear regulators on some old hardware might not like ultra-low ESR polymers as much... but that's super-rare. As for the 6.3V 1500 uF Panasonic caps from the 2nd link - again, those would also be fine for both the 1000 uF and 1500 uF caps if you have more of them. I know going from 1000 uF to 1500 seems a bit too much, but IME most boards don't care. Manufacturers don't do it simply because it costs more and is not really needed. I tend to do it when I'm out of specific size/capacitance caps (very often) and just want to test the hardware or get it fixed quickly.

[ssl6]

Re: MSI K7T266 Pro (Ver. 1.0)

alright, that works for me. I guess I'm placing a digikey order though. Based on stock and pricing in Canada, I'm going order these to replace those Tayeh and Chhsi

https://www.digikey.ca/en/products/d...0J152B/7381147
https://www.digikey.ca/en/products/d...8X11-5/3563379