Unhappy Octane frontplane, capacitors leaking. Anyone spec'ed replacements?

SGI hardware problems, solutions, tips, hacks, etc.
Forum rules
Any posts concerning pirated software or offering to buy/sell/trade commercial software are subject to removal.
User avatar
halfmanhalftaco
Posts: 28
Joined: Wed Jan 25, 2017 7:40 pm

Unhappy Octane frontplane, capacitors leaking. Anyone spec'ed replacements?

Unread postby halfmanhalftaco » Fri Jul 07, 2017 6:54 pm

I have an Octane FP1 that doesn't go, I think it is a very early version: REV A with a 9726 datecode on it. It seems like it almost wants to work, but I can't get it to boot farther than lighting up the BaseIO and QA LED (no Heart LED). I've tested all of the other components (IP30, PSU, graphics) in another Octane and they all seem to function fine on a different FP1.

Pulled the FP1 out and quite a few of the SMT electrolytics are unfortunately leaking, particularly the ones on the side the IP30 plugs in :(

Image

Most of them appear to be 330uF 6.3mm SMT caps with the marking "6D 330 6X". I haven't been able to figure out what manufacturer/etc. so I can track down a datasheet to select some replacements. Can anyone identify these? There are 42 of them on this FP1. The other 7 capacitors are smaller 4.7uF 4mm SMT caps labeled "6N 4.7 35X"

I just want to make sure if I buy replacements and attempt a repair on this that I'm buying caps that are spec'ed at least as good as the originals.

Thanks for any assistance you guys may have.
:Indy: :Indigo2: :Octane: :Octane: :Octane:
Indy XL24 R4600SC 133MHz | Indigo2 Extreme R4400 250MHz | Octane MXI 2xR12000 300MHz
2x Octane SE 2xR10000 195MHz
SPARCstation 20 SX 2x125MHz HyperSPARC | SPARCstation 20 TurboGX+ 2x60MHz SuperSPARC-II
SPARCstation IPC GX 25MHz SPARC | SPARCstation IPX GX 40MHz SPARC | SPARCclassic TurboGX 50MHz microSPARC
SPARCclassic X cg3 50MHz microSPARC | Sun Blade 100 Expert3D-Lite 500MHz UltraSPARC IIe
JavaStation-1 (Mr. Coffee) 110MHz microSPARC-IIe
https://halfmanhalftaco.com/inventory/

User avatar
vishnu
Donor
Donor
Posts: 3174
Joined: Sun Mar 18, 2007 3:25 pm
Location: Minneapolis, Minnesota USA

Re: Unhappy Octane frontplane, capacitors leaking. Anyone spec'ed replacements?

Unread postby vishnu » Sat Jul 08, 2017 12:01 pm

That's a Panasonic Aluminum SMD series capacitor, but that diode looks pretty darned unhappy too, looks like it got too hot but the board underneath it doesn't look charred, and why does the silkscreen say "CR" if it's a diode??? :?: :?:
Project:
Temporarily lost at sea...
Plan:
World domination! Or something...

:Tezro: :Octane2:

robespierre
Posts: 1553
Joined: Mon Sep 12, 2011 2:28 pm
Location: Boston

Re: Unhappy Octane frontplane, capacitors leaking. Anyone spec'ed replacements?

Unread postby robespierre » Sat Jul 08, 2017 2:30 pm

SMD electrolytic capacitors are made in standard sizes, so you need to measure the diameter (as with a caliper).
They also have standard capacitance and voltage series. One problem with markings is that each supplier uses a different convention: some will print the capacitance in uF, while others print the capacitance code with a multiplier. This is a particular problem with "100" and "330" since both 10 uF and 100 uF, 33 uF and 330 uF are part of the standard series.
"6" means 6.3V rating.

Vishnu: "CR" is pretty common on silkscreens. It originally meant "crystal rectifier" but is now used even for silicon diodes.
:PI: :O2: :Indigo2IMP: :Indigo2IMP:

User avatar
halfmanhalftaco
Posts: 28
Joined: Wed Jan 25, 2017 7:40 pm

Re: Unhappy Octane frontplane, capacitors leaking. Anyone spec'ed replacements?

Unread postby halfmanhalftaco » Sun Jul 09, 2017 11:19 am

Thanks, I did measure the diameters as shown above, but I'm trying to definitively determine the capacitance and some other parameters (like ripple current rating, ESR, etc.) I suspected they were 6.3V based on the '6' markings but thanks for confirming that! I guess I should probably just select the best-specification caps I can find in that size/capacitance. I usually go Nichicon or Panasonic when it comes to regular through-hole radial electrolytics but I've never dealt with SMD electrolytics, are those still good brands?

I *think* they are 330u and 4.7u but like you said, the multipliers/etc. can vary among manufacturers. I may try to remove one that still looks good and measure it just to confirm my suspicion.

I'd hate to buy 100 or so 330uF caps only to find out that I needed 33uF! (Edit: pulled one of the "330" marked ones off and measured it with my Fluke, it read at 366uF so definitely they are 330uF caps and not 33uF caps)

I may be overthinking this, especially since all of these caps appear to just be decoupling capacitors, but the amount of effort that I'll have to put into actually removing and replacing these (with little guarantee that it will fix the problem) makes me want to make sure I'm getting right parts.
:Indy: :Indigo2: :Octane: :Octane: :Octane:
Indy XL24 R4600SC 133MHz | Indigo2 Extreme R4400 250MHz | Octane MXI 2xR12000 300MHz
2x Octane SE 2xR10000 195MHz
SPARCstation 20 SX 2x125MHz HyperSPARC | SPARCstation 20 TurboGX+ 2x60MHz SuperSPARC-II
SPARCstation IPC GX 25MHz SPARC | SPARCstation IPX GX 40MHz SPARC | SPARCclassic TurboGX 50MHz microSPARC
SPARCclassic X cg3 50MHz microSPARC | Sun Blade 100 Expert3D-Lite 500MHz UltraSPARC IIe
JavaStation-1 (Mr. Coffee) 110MHz microSPARC-IIe
https://halfmanhalftaco.com/inventory/


Return to “SGI: Hardware”

Who is online

Users browsing this forum: No registered users and 3 guests