underclocking an old pentium 200

[KvHagedorn]

I suppose you could heat a fairly large swimming pool (in Moscow, in January) with that...

[rylan]

thop, there certainly is 70ns EDO memory. I have a bunch of the crap at work sitting in a pile.

Anyway, as mentioned an 80mm fan should be fine to replace the bad one in the PS. OR you can just but a new cheapo 200w or so AT supply. Just be careful when hooking up the power switch to get the polarities correct.

[TdB]

well, I managed to get the machine up and running, with spareparts from other old computers.

It plays dosgames quite nice, I have completed "heretic" and "shadow caster" so far.

however the computer is very noisy, so my original question still stands, (the one about underclocking).
I plan to underclock the hell out of it, and see if it would be possible to replace the fans with passive cooling. (dosgames doesn´t NEED 200mhz anyway ).

my question is: would it be possible to replace the cpu-fan with a fanless heatsink(and what kind of heatsink should i use for a socket 7 cpu?), if I underclock it to 66mhz(or even 50mhz, if I underclock the bus too) or is that just too crazy?

another question: does fanless PSU´s exist, and if so can they work with an AT-case?

the computer supports powersaving, which means the harddisk turns off after a minute, so the harddisk is a non-issue(especially because I have 64mb ram, which is enough for every dos-game).

Is it possible to make this computer 100% silent? what do you think?

edit: just found this: http://www.silentmaxx.de/nt_prosilence_fanless.php
it is just too expensive
can an ATX PSU work in an AT case with an old pentium, I mean are ATX PSU´s backwards compatible?

[Kurt]

Zalman 8cm silent fan that you attach on top of the pci/isa slots. depending where the cpu is, there's probably a way to turn the fan in such a way that it'd blow air on it.

[TdB]

well, I was actually thinking of a completely fanless system...

just to see if it was possible...

[Ribbit]

Originally posted by TdB
(dosgames doesn´t NEED 200mhz anyway ).

It's not all that high for EF2000

[Ribbit]

Originally posted by TdB
can an ATX PSU work in an AT case with an old pentium, I mean are ATX PSU´s backwards compatible?

I think the screw locations are the same, so if the motherboard is ATX then that would be fine. But then I don't think an ATX motherboard will fit in an AT case, so I think the answer to what you're asking is no.

Damn you, now I've confused myself.

[TdB]

the motherboard is an old AT motherboard, just as the case is an old AT-case.
the reason I asked is because I think a fanless AT PSU might be hard to find.

it is just an old pentium

BTW, it doesn´t have to be pretty, so the actual question is: will an ATX PSU work with an AT motherboard,(does it have the right plugs?).
I can live with an "external PSU", but a PSU that fits inside the case would be preferable.

[Ribbit]

Oh, in that case no. ATX PSUs won't work with AT boards.

[TdB]

so I will have to mod the AT PSU myself?

is that doable?

it sounds kinda risky...

[Byock]

It is doable, but risky. And Ribbit is quite right, ATX power supplys have a single honeycomb power connector, while AT have 2 smaller connectors.

[TdB]

hmm, looks like my experiment will require some serious research...

BTW, I just discovered that it actually have EDO ram, don´t know the speed yet.

[bsdgeek]

I don't see why you'd need to underclock, they don't produce that much heat. I had a K62-380 run with a puny heatsink and the fan unplugged for years before I even noticed it was "fanless"...

[TdB]

hmm, my idea was that an underclocked CPU didn´t draw as much power from the PSU, which would allow me to make the PSU fanless too.

[bsdgeek]

A P200 doesn't draw that much power, I would guess less than ~20W or so.