VOGONS


Asus P2B-DS Rev 1.06 FSB Modification

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Reply 41 of 63, by wiretap

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My little tiny PCB's finally arrived, 🤣. Don't know when I'll have the time to do this, but I'll give it a go sometime in the future.

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Reply 42 of 63, by wiretap

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After a quick look at my board, I have the 1.06 D02 revision. I'll have to source a ICS 9250CF-08 for this, since it currently has the ICS 9150AF-08. It should be an easy swap, and I probably have one in a scrap board in the basement.

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Reply 44 of 63, by Mamba

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wiretap wrote on 2021-01-22, 17:23:
My little tiny PCB's finally arrived, lol. Don't know when I'll have the time to do this, but I'll give it a go sometime in the […]
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My little tiny PCB's finally arrived, 🤣. Don't know when I'll have the time to do this, but I'll give it a go sometime in the future.

v3E1jHL.jpg

rCavlGZ.jpg

Can't wait to see it done.

Reply 45 of 63, by wiretap

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Found some new ICS 9250CF-08 chips for $4ea, so I ordered 5 of them. My mod will be ready to install when I get a break. I'll probably bundle the other 4 PCB's into a kit and throw it on a marketplace once I confirm it works.

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Reply 46 of 63, by wiretap

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I'll be testing once I get the ICS 9250CF-08's and get that soldered in.

So this little thing just plugs into the existing jumpers, then transposes them and adds the 4th needed jumper for 133MHz FSB. The R99 pad obviously connects to the motherboard's R99 resistor with a jumper wire.

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Reply 48 of 63, by wiretap

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Old frequency generator removed:
pzQTVjX.jpg

Pads cleaned:
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New frequency generators:
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New frequency generator in place:
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New frequency generator soldered in place with the mod PCB test fit on the jumpers. Perfectly fits next to those capacitors without touching. 😁
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Reply 49 of 63, by wiretap

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R99 hooked up. I couldn't find my 36ga wire, so I had to use 24ga which looks giant, 🤣. I'll replace it once I go through some boxes.

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Reply 53 of 63, by wiretap

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Well, no dice on the testing. I believe the frequency generators are counterfeit. The text on top of them comes off with isopropyl alcohol and the motherboard doesn't even post with the new chip installed. I put the old chip back on and the motherboard boots just fine. Testing on hold until I can source a legit frequency generator.

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Reply 57 of 63, by pshipkov

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Bummer.

Actually i remember having a 1.06 D02 board that did not like the 9250 clock gen for some reason. The chip got warm, but board didn't post.
Same chip worked on 1.05 revision, for example.
No idea why.

Is the FSB control board sitting stably on the 3 jumpers underneath when pushing or pulling jumpers ?

Btw, if you cannot find clock gens nearby - i have few that collect dust here. Can send you 1 or 2 at no cost.

retro bits and bytes

Reply 59 of 63, by wiretap

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@pshipkov -- that may be the case with incompatibility for some odd reason. The chip does get warm, but no post. As far as the little board, it is pretty sturdy. I pulled jumpers off and put them on with one hand, just holding my thumb on the motherboard connector side. It does lean a little bit, but it doesn't fall of the board and has a good amount of friction-fit.

@Mamba -- I didn't test that, since this mod adds the 4th row of jumpers which specifically takes advantage of the 9250 clock gen. The 4th row would not map to anything on the old one.

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