If you really want to make your de-soldering job quick and easy, invest in one of these. It's the best money I've spent in a long time.

$112.99 + free shipping

http://www.ebay.com/itm/S-993A-110V-90W-Elect … -MAAOSwPhdVGfpT

MMaximus wrote:

Really cool story - thanks for sharing! Brings back memories as I had a P90 with the same board and 8megs of RAM in 1994 as well. When a few years ago I decided to use it again after a 15 years or so hiatus, it worked for a few months and then the Dallas RTC finally gave in. I bought a replacement chip but being quite discouraged by the soldering involved I decided to give it away to Devius... who seem to have successfully replaced the RTC 😀

Here are a few pics of the system:

Highscreen Vobis "SkyTower" Pentium 90 - CT1750 & SCC-1

Thanks, I enjoyed reading your thread as well. There were so many parallels between our P90 experiences; even that we both had S3 864 video cards. Sorry that you gave yours away.

Brickpad wrote:

If you really want to make your de-soldering job quick and easy, invest in one of these. It's the best money I've spent in a long time.

I've already decided to go that route! I ordered a ZD-985 this morning. I figure I need to replace some RTCs on some networking gear and I the videos I saw on youtube make it look so easy. Having the right tools makes all of the difference.

Here's the Pentium Overdrive I got for this system. I really like that its fan is powered from the socket itself. Unfortunately it doesn't boot up with the Overdrive. The keyboard lights flash once, but that's all. It came with a disk and it might have a BIOS update so the overdrive will work. I'll check it out tomorrow.

FFXIhealer wrote:

So disappointed. When I read P90, I thought of this […]
Show full quote

So disappointed. When I read P90, I thought of this

Hands down best gun

Very nice write-up! I enjoy reading through these socket 5 and older rebuilds. Reminds me of my mid-90's computer life. I too went with a Matrox Mystique 4 MB, although this card doesn't seem to get much praise on this forum. Are you going to max out the system RAM?

I wouldn't feel too bad about the switcheroo. Even today, I have bought Honeywell thermostats, LCD bulbs, etc which died just after the store's 30 or 90 day return policy. It is such a hassle to mail them in to the company for a replacement. Simplicity dictates buying a new one of the same model and returning the defective one in the new one's packaging. The store's don't normally loose money on this - they return it to their supplier.

I am surprised that the store did not contact you after the supplier noticed the difference between the S3 864 vs. 868. I guess the hassle wasn't worth the cost difference.

Brickpad wrote:

If you really want to make your de-soldering job quick and easy, invest in one of these. It's the best money I've spent in a lon […]
Show full quote

If you really want to make your de-soldering job quick and easy, invest in one of these. It's the best money I've spent in a long time.

$112.99 + free shipping

http://www.ebay.com/itm/S-993A-110V-90W-Elect … -MAAOSwPhdVGfpT

Tempting, but is there no temperature set gauge?

feipoa wrote:

Very nice write-up! I enjoy reading through these socket 5 and older rebuilds. Reminds me of my mid-90's computer life. I too went with a Matrox Mystique 4 MB, although this card doesn't seem to get much praise on this forum. Are you going to max out the system RAM?

I wouldn't feel too bad about the switcheroo. Even today, I have bought Honeywell thermostats, LCD bulbs, etc which died just after the store's 30 or 90 day return policy. It is such a hassle to mail them in to the company for a replacement. Simplicity dictates buying a new one of the same model and returning the defective one in the new one's packaging. The store's don't normally loose money on this - they return it to their supplier.

I am surprised that the store did not contact you after the supplier noticed the difference between the S3 864 vs. 868. I guess the hassle wasn't worth the cost difference.

Glad you enjoyed it! The Mystique was an upgraded Millennium right? They weren't out yet when I bought this computer and they were definitely out of my price range. But I remember drooling over the Impression's 3d capabilities. And yes I plan on maxing out the RAM and seeing what operating systems it can run.

I don't think the store had my phone number. But I did use my mom of dad's credit card.

feipoa wrote:

Brickpad wrote:

If you really want to make your de-soldering job quick and easy, invest in one of these. It's the best money I've spent in a long time.

$112.99 + free shipping

http://www.ebay.com/itm/S-993A-110V-90W-Elect … -MAAOSwPhdVGfpT

Tempting, but is there no temperature set gauge?

The temp setting is that little round thing on handle (that's what she said.)

I went for a ZD-985. https://www.youtube.com/watch?v=Ft50m8UU5WQ

With the soldering pump (the manual one) there's the danger to ruin your traces. It's kickback may strike the tip of the soldering iron against the PCB, scratching or cutting traces.

If you have steady hand, it is usually not a big problem, I use it for two years, and its job was awesome everytime. But I have aluminium one, also had plastic, and had to throw it away, it was garbage.

I use this. It's very cheap and works great. Not temperature controlled but it's very quick at desoldering.

$14.99 at Radio Shack.

Really nice retrobox you got there. It's always great to see how nice and clean you can get older machines to look.

keenerb wrote:

https://cdn.shopify.com/s/files/1/0953/5270/products/06402060_00_600x600_crop_center.progressive.jpeg.jpg?v=1446834230 […]
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I use this. It's very cheap and works great. Not temperature controlled but it's very quick at desoldering.

$14.99 at Radio Shack.

I bought one of those as well, but I killed one of my FIC boards after it severed a trace. Haven't used it since then. I would stay away from that.

I don't honestly know how you managed to sever a trace with it. It's just a soldering iron with a vacuum.

Unless you just didn't desolder completely and pulled the trace off the board. You can do that with any desolder tool.

keenerb wrote:

https://cdn.shopify.com/s/files/1/0953/5270/products/06402060_00_600x600_crop_center.progressive.jpeg.jpg?v=1446834230 […]
Show full quote

I use this. It's very cheap and works great. Not temperature controlled but it's very quick at desoldering.

$14.99 at Radio Shack.

I don't do much soldering work since I'm not that confident in my skills but I use one of these and I've never killed anything with it.

Back on topic, sort of...

I scoured the Internet looking for information to whether or not the Pentium OverDrive is compatible with this motherboard and found conflicting answers in ancient usenet posts. One guy, from Intel, said that only the official 66Mhz FSB (100Mhz Pentium) was compatible. And another guy replied to say he was wrong.

Here is the OverDrive installed and powered on.

The guy from Intel was wrong. All it needed was the latest BIOS (.16AX1) and it started right up! I was really doubting it would work. It shows up as a Pentium 66 in the BIOS, but who cares because it works!

Here's the diagnostic program from the OverDrive floppy. It shows useless before and after information and then runs a simple benchmark where it draws a fractal image.

I'm not sure I'm going to keep the OverDrive in this box, since it wouldn't be a P90 anymore. But it's fun to play with. So far I've run some games (Quake, Descent) and there are some nice speed increases. Also, I had some SNES emulators on that Maxtor and games run silky smooth.

I think I'm going have to upgrade the ide controller because it's slowing the system down. Maybe get a SATA controller that hasa BIOS.

In other news, the ZD-985 had been shipped. More on that later.

I got my ZD-985 Wednesday, but I didn't get a chance to play with it until today. In preparation for the big RTC replacement, I practiced removing components on an old, and zapped by lightning, ISDN terminal adapter. I guess this could be considered my retro activity for the day.

As you can see, it works like a champ. I found that 350C is a good temperature for this unit. But I have no idea how accurate the sensor is.

Here's the patient ready for operation. The Kapton tape is there in case there are any mishaps.

The RTC is removed. It was actually harder than expected. What I should have done, and recommend you do, is add new solder to every joint before using the desoldering gun. I had to redo five joints this way. Other than that, there were no problems and no damaged traces or pads.

The socket is installed and soldered. This is a multi-layer board and there are pads on both sides, so I applied non-corrosive flux on both sides. Soldering took
two minutes at most.

I powered it up after installing a "new" RTC and I got a dead CMOS battery message! Luckily I had four others to try and the next one worked fine. I'll order some new DS12887+s from either Maxim or online store to replace these from China. To be honest, I think these are counterfeit. The silkscreening doesn't look right.

That's not the end of this thread. There is still a lot more work to be done to this P90. I have to decide whether or not to put a network card, USB 2.0 card, or SATA adapter. And which ones? 3c905B, NEC USB 2.0 card, and some generic SATA controller that has a BIOS perhaps.