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Posted by: CC_333 on 2012-04-01 15:16:06 Hi, All, I have here some sort of card (accelerator?) that was installed in my new-to-me Mac IIfx. Google is unable to give me relevant information. However, I do know that it is manufactured by Newer Technology, as it is printed on the bottom side of the card (see photo). Here is what I have learned so far through a visual inspection: It has a socket on top, inside of which the original 40 MHz 68030 CPU was installed. The pis on bottom connect to the Mac IIfx CPU socket. On top of the cards PCB, there is a two pin header, to which a pair of wires attach. The other ends have small clips, which attach to diagonally opposite pins of the Mac IIfx clock oscillator. It has four oscillators of its own, each 10 MHz faster than the first, with a range of between 80 and 110 MHz. Here are some photographs: Top view of card. Notice the four clock oscillators: Bottom view of card: c
Posted by: Trash80toHP_Mini on 2012-04-01 21:21:38 I'm glad to see you've posted these pics with a clear explanation. When I first saw them I wondered if those two covered ICs might be SRAM Cache? ROM and, if so, why? :?: Dunno, strange beastie! :approve: Apparently this card throws off enough RFI to preclude a "Class A" FCC homeroom pass. 8-o
Posted by: Strimkind on 2012-04-01 23:23:36 This could be a Variable Speed Overdrive that Newer Technology manufactured for various 68k machines including the IIfx. With the multiple oscillators and the wires connecting to the original on the logic board, it makes sense.
Posted by: olePigeon on 2012-04-02 13:42:20 So did it allow you to set the MHz without rebooting the machine?
Posted by: CC_333 on 2012-04-02 16:48:35 So did it allow you to set the MHz without rebooting the machine? I can't know until I get a video card (until then, the machine's rather useless). This could be a Variable Speed Overdrive that Newer Technology manufactured for various 68k machines including the IIfx. With the multiple oscillators and the wires connecting to the original on the logic board, it makes sense. Variable speed does make sense, but as I said above, I can't know until I get a video card. It also has a big red momentary button on the side closest the CPU socket (see photos). I wonder what that does? I've speculated that it could be one of two things: a secondary reset switch, or a speed selector (it seems more logical that that would be done in software, though). Once I get a video card, I will definitely play around with it and see what it does. Until then, it's pure speculation. c
Posted by: Trash80toHP_Mini on 2012-04-02 19:41:58 I'll have to get a move on in the process of choosing, testing and shipping your card set! :approve:
Posted by: ClassicHasClass on 2012-04-02 21:10:58 "FOR BUSINESS USE ONLY," lol! :lol:
Posted by: CC_333 on 2012-04-02 21:36:51 "FOR BUSINESS USE ONLY," lol! :lol: I know. When I saw that, I wondered why it was there. I didn't think about it much beyond that, though. I'll have to get a move on in the process of choosing, testing and shipping your card set! :approve: No rush. c
Posted by: Bunsen on 2012-04-09 10:17:50 There's a picture of an 040 version here. It does indeed look pretty similar.
Posted by: CC_333 on 2012-04-09 10:46:05 Bunsen-- Yes, it does look similar. Perhaps it is designed for such use, but the previous owner instead took out the upgrade's original CPU (an '030?) and used the IIfx's CPU instead. Note, however, that it doesn't have any provision for an FPU. It came with a fan, similar to the one in your picture, but it was badly installed (a big mess of thermal compound and hot melt glue that broke loose), so I removed it (it shouldn't need one unless it is clocked really high, I don't think) Kind of a mysterious little piece of history here! Once I get a video card, I'll try it out. c
Posted by: CC_333 on 2013-05-03 22:28:13 Sorry to dig up an old thread (it is mine, though :🙂 ). No new progress on this thing. A lot has been going on this past year, so I never really had the time to devote to it. Hopefully I can squeeze it in sometime soon, though! By the way, does anybody know of a good and secure (but removable) type of thermal adhesive I could use on the thing if I install it in the IIfx? I'd like to install its little fan if I can (it must've been there for a reason). c
Posted by: markyb86 on 2013-05-04 21:16:28 Arctic silver makes an awesome two part adhesive, but that stuff doesn't want to come off... it's really on there!
Posted by: James1095 on 2013-05-06 12:48:31 Use ordinary thermal paste in the middle, with a tiny dot of adhesive on the edge. They make double sided thermally conductive tape but it's hard to find.
Posted by: olePigeon on 2013-05-06 13:15:20 Will that work with any 040? Or just the Quadra? Could you sandwich the 50MHz overclock onto a Daystar Turbo 040?
Posted by: CC_333 on 2013-05-06 13:36:57 Will that work with any 040? I doubt it. It came from a Mac IIfx, so it is for an 030. Could you sandwich the 50MHz overclock onto a Daystar Turbo 040? Probably not. See above. Use ordinary thermal paste in the middle, with a tiny dot of adhesive on the edge. And it will be "undo-able" this way? Arctic silver makes an awesome two part adhesive, but that stuff doesn't want to come off... it's really on there! Yeah, I don't want it to be permanent, but I do want it to be as secure as I can get it without external clips, yet removable. c
Posted by: Bunsen on 2013-05-11 05:40:41 Cable ties?
Posted by: Trash80toHP_Mini on 2013-05-11 06:08:05 Use ordinary thermal paste in the middle, with a tiny dot of adhesive on the edge. And it will be "undo-able" this way? Make that a tiny dot of crazy glue gel at each corner an you'll be set. Use a brush to wick a bit of lacquer thinner to each of the dots in rotation a few times and then twist it off to shear the bonds instead of prying it apart to break the bonds under tension.
Posted by: CC_333 on 2018-04-09 20:22:14 Well, I sure dropped this one! I never got around to testing it, and it's been floating around in my closet for the last five years or so. Last week, joethezombie contacted me, asking what the little doughnut-shaped thing is next to U12 (some sort of simple ferrite core, I think), and this has gotten me interested in it again, but guess what? I packed my IIfx! sigh At least it has a video card now (and a network card 🙂 ). I'll get to this eventually! c
Posted by: ArmorAlley on 2018-04-10 06:21:34 There is still a link on the Newertech website to the Variable Speed Overdrive IIfx https://www.newertech.com/downloads/Software/VSO_IIfx.sit It's on the Legacy Support page: https://www.newertech.com/tech_support/support_legacy.php If it is a VSO, then this page might be useful: https://archive.info-mac.org/info/hdwr/quadra-700-clock-mod-145.txt
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