Re: buy second-hand abit kt7a-raid?

I found that the hardest caps to replace on the KT7A are the two caps between the AGP slot and adjacent PCI slot. They are two 1500uf 6.3V caps, and they are right next to each other, and between two slots, so they are more tricky than the others since there is less room to manoeuvre and also difficult to see where the leads are going.

I have two of these boards, and my experience seems to suggest that the three 1500uf 6.3V caps near the AGP slot are the first to go bad.

On 1 of my boards, they were bulged, and after...

This board was completely covered with Wendell brand capacitors, mostly 1000uf 6.3V and 1500uf 6.3V. Every single one of these were bulging.

Of course the machine had gotten extremely unstable and would reboot itself or park the IDE drive randomly.

I recapped it with Rubycon MBZ's, 1500uf 10V and 1000uf 10V. The machine works GREAT now, although the BIOS hardware monitor now says that all the voltages are higher than what they should be... e.g. 12V rail reads 12.5, etc. Not sure if this is a side effect of using 10V caps, as I don't remember if the hardware monitor...

I have two of these boards, an Abit KT7A and a KT7A-RAID. The KT7A is about a year older than the RAID.

It seems to me that the first caps to go on these boards are the three 1500uf 6.3V ones near the AGP slot. On my KT7A, these were bulged visibly (Jackcon brand). On my KT7A-R, these didn't show any visible signs of deterioration, but I kept getting blue screen errors that referred to an Nvidia driver, and the machine was generally unstable.

After recapping both boards completely with Rubycon MBZ series, they are running remarkably well.

Interestingly,...

Re: Tyan Trinity KT S2390 - VRMs? Capacitors?

After a couple of hours of use, I heard "click click" and the machine froze, then I got that lovely burnt electronics smell.

I didn't see any components with any burn marks, so I decided to recap the board and try again. After recapping the board, the machine booted up fine, all the voltages seemed great. I was constantly monitoring the Vcore voltage, which was at 1.79V (even though BIOS says 1.83!). Then the machine froze again and I noticed at that moment that the Vcore dropped to 1.4V or so.

...

Re: Tyan Trinity KT S2390 - VRMs? Capacitors?

I took a chance and plugged in a known working CPU I had, a Duron 1.1 Morgan core. The Morgan core CPUs aren't officially supported on this board.

I was surprised when I powered it on and heard some error beeps - i.e. missing RAM! The voltage across the caps near the CPU read 1.78V which is not too far from the 1.75 spec of the Morgan core.

I put in a stick of RAM and an AGP video card and the board boots, recognizing this supposedly unsupported CPU as an Athlon 1.1GHz.

Three different sticks...

Re: Tyan Trinity KT S2390 - VRMs? Capacitors?

So... what does that mean... if they're not shorted... then it may be safe to plug a CPU in there?

Re: Tyan Trinity KT S2390 - VRMs? Capacitors?

Here are the pics...

No I'm not sure the CPU is toast, but it has been misplaced, or so my friend says.

I do recall trying to diagnose it months ago, that at one point I could swear I could smell a faint smell of something burning, and I did think at the time that the CPU heatsink, for a Duron 700, was unusually hot! So I would not be surprised if the CPU was in fact toast, and that's also why I am reluctant to pull off a good working CPU in one of my other machines to test it!

OK, I checked...

A friend of mine was going to toss out a Tyan Trinity KT S2390 board. It stopped booting up one day, and he later ended up buying a new motherboard and CPU. The computer store told him that his CPU had gone bad and they said it was likely that the board fried the CPU since the heatsink and fan were all properly installed.

I should say that I've successfully recapped 3 mainboards so far (with Rubycon MBZ's) - two Abit KT7A's and a Soyo 7VEM, which all seem to be working better than they did when brand new.

I've looked at this Tyan board, and none of the capacitors...