i486 DX2 ???

Hey there... a friend of mine gave me an old pc
I tore it apart of corse & it has an i486 dx2 processor the numbers on the TOP side of the chip are

a80486dx2-66
L5243527
&EW5V1X SX955

bottom side of chip are

95175274AC
MALYA
GH 525

I66

Is this a 525mhz Processor with a 66mhz FSB ? or just a 66 mhz processor

also would it be worth building a small rig around this processor & what would it be good for or is it basicaly scrap for the history pile ???

I guess if its a 525mhz processor it would be good for a kid some how I think its a 66mhz processor tho & I dont think that would be good for much except powering my Phone LOL if that

a 486dx2 is definitely no 500+ mhz processor...that is likely a 66 mhz processor....

now that's pretty slow for many things...

but then you might find a use for it

actually, i used a 486 dx2 at university of maryland in 1991 and i had to do extensive monte carlo programming with many embedded loops...most programs took 6-8 hours to complete----

then i got my third computer...a dell pentium 90 with 8 mb ram!!!

believe or not that pentium 90 was much faster...the program only took 1.5 hours...

i bet my computer now would do that program in a couple of minutes...

LOL so its basicaly junk

cozmo_d said:

LOL so its basicaly junk

Click to expand...

use it as a router or something

The 486DX2 was great in its day....but that was long ago.

I believe it is a 66MHZ chip with a 33MHZ Bus ( 33 X 2 = 66)

Good old VESA local bus, that brings back memories......lol

The 486 line came in four bus speeds: 25mhz, 33mhz, 40mhz, and 50mhz. There were no single-digit increments, you had only these choices. I think technically there was a 20mhz speed, but I only remember seeing one or two machines with uber-slow speed as an option...

486 chips came in an both DX and SX flavors (with or without math coprocessor, respectively). In the beginning, 486 processors ran at the same speed as their bus. A bit later, they began making DX2 and SX2 processors -- chips that ran at double the bus speed (again, with and without math coprocessors). These came in SX2/DX2 50mhz (25x2), SX2/DX2 66mhz (33x2). This was the first time Intel ran their mainstream processors asynchronously from the bus.

Once the Pentiums started coming out, Intel also gave 486 owners the option to use a DX4 chip. These came in DX4/75mhz (25 x 3) and DX4/100mhz (33 x 3). Yes, I know it's not a 4x multiplier, don't ask me... Intel was dumb

AMD also pumped out a few of their own AM4x86DX4 chips: in 100mhz (50x2, or 33x3), 120mhz (40x3) and 133mhz (33x4). Several people were able to overclock the 120 chip to 150 (50x3) and quite a few got the 133 chip to 160 (40x4)

Intel's last suppliment to the 486 architecture was the "Pentium Overdrive" chip, which came in 63mhz (25 x 2.5) and 83mhz (33 x 2.5) flavors. It was actually a somewhat hacked Pentium core made to stick on the 486 architecture. The 83mhz one was actually on-par with the Pentium 75, which wasn't awful at the time The AMD DX4 chips were almost always faster than those however.

My AMD DX4/120 ended up performing about on-par with a P90, and when overclocked to 150, it would perform just a tad below a P120. Back in the day, this was goooood stuff

its scary to think about processors only being considered faster when they've only got a 10mhz edge. back in the day.......

Yep, that's a 66 MHz 486, a speedy system back in it's day (mid-90's) considering lots of 486 rigs were only 33 MHz. I still get a few of those old 486 machines given to me. Know what I do with 'em? Pull the 3.5" floppy drive out of 'em and throw the rest in a dumpster.

I still have an evil urge to slap a 100-watt pelt onto one of those DX4/133 chips and overclock that ******* to 200mhz. I don't even know what a 200mhz 486 would perform like, but dammit I'd find out!

Get one of those uber-elusive 486 boards with the PCI slots, slap in my old Riva 128 PCI card and my Voodoo Original card and I bet it would almost be a decent performer

I mean, for a 200mhz processor that is

LOL

Some great history amazing to think thoes were hot in the 90's
some 13 years later & were smokin that big time

wonder what the next 13 years has in store

Guys,
this is a very old thread, but I have a very old machine I just pulled out of my basement. A dell 486 DX2 with a 66mhz chip. It runs fine and still works with most software from 3.1 to Win 95 with a cut-off about the year 1997 when games are asking for chips above 100mhz.

My question is whether the 66chip can be replaced with one of the later chips that bring it to close to double it's current speed. This is the difference between playing Curse of Monkey Island or letting LeChuck freeze Threepwood in his tracks! I am also going to build a retro Windows 98 machine, and one for XP, but I want to take this 486 to a place few 486s have gone before. (has only ISA slots but that won't stop me.)

Thanks for any help!

I seriously doubt that chip will run windows 98...or even windows 95 for that matter. I remember windows 98 running pretty well on the Pentium Pro my family had back then. Before that we had a 486SX which ran at 33mhz I believe, it was great for running dos 6.x, was perfectly usable in windows 3.1, but wasn't good for much else later on.

Thanks for the quick reply tachi1247!

I have already upgraded the maching to Windows 95 and it is working very well on software written up to about 96/97. The windows 98 machine is a separate project. My question is whether or not there is a later 486 architecture chip I can replace the 66mhz chip with to bring the speed up to 100/120mhz. You understand that this question is not a strictly practical one. I just want to push it a bit.

I used to have a Compaq Presario 425 (486SX 25, 4MB, 200MB) upgraded to DX/2 66, 20MB and 500MB, I also owned faster (DX4 100 and a couple of compatibles, Cyrix and AMD, I think) but I'm pretty sure there was some, possibly valid, reasons that I didn't test the faster chips. It ran (a stripped down) W95 second release fine, pretty snappy, actually.

Thee are a range of chips from various makers above the 66 that would be 'compatible', from 80 - 100 - 120 - 133 - 150, along with an Overdrive or two.

I'll buy the thing off you, got a nostalgia moment here (had a 486 33). Still have the DOS 6.22 and Doom floppy's somewhere I believe

Thanks for the offer Kenrow, but I plan to keep it. I have boxes and boxes of software from that period to keep alive. However, if you have an old functional win98 desktop, I might buy that from you?

Clock speeds advanced so quickly I assume that the reason you never tested those was that faster cpus and boards were already available? Looks like the AMD dx4 probably gives the most bang to the board? I assume that there is nothing further I could do to the dx2 66 cpu that is already installed?

I think there was a likely physical (voltage?) issue with the Compaq 'board and also a reluctance to increase the heat levels (it was an AOI, with the 'board in the base, limited space for cooling). I was already running a Duron 800 by the time I had the 325.

I'd push for a 100Mhz or better in your rig, the AMD's were pretty good, as was the DX4 100.

The 66 could, if you were lucky/careful, be clocked by a few Mhz or more, depending on the BIOS.

Yes, I read the voltage has to be reduced from 5V to 3ish on the later cpus. Also read that the AMD and Cyrix cpus had special jumpers on the later 486 boards. My '93 Dell board does not have those jumpers so I think I will go with the Intel DX4 100 chip to assure compatibility.