CompuServe Thread

#clock speed doubler chip

7 messages in this thread
#9418From: Larry MintonFeb 19, 1992 11:02 AM
They will market them as 50MHz of course. Just look at tape drives – 250 meg is really 125 meg with data compression. A 487SX is really a 486DX with a different pinout. Hmm.. I wonder if there is any real difference between a 486SX and a 487SX? Maybe they just didn't hook up one wire on the inside. Cynically yours, Larry
#9421From: Jay Parisi [Anim/Gra TM]Feb 19, 1992 12:07 PM
Larry, You're right about the 486SX being the same as a 487SX. Intel disabled the Coprocessor on the 486SX, but it was STILL THERE!! At least this is how they did it on the first 486SXs. Now they might not have a coproc. This is why 486SXs are called "Brain Dead". How a company can take a good product like a 486, go through *extra* steps to disable part of it, change the pin out, and slow it down, and then sell it cheaper than it was when they started is beyond me. I think just lowering the price of the regular 486DX would have been better. The absolute *worst* part is when you plug a 487SX in you *disable* the 486SX!! You now have a several hundred doller hunk of silicon doing *absolutly nothing*!! Jay
#9431From: Evan Yares [WeirdTM]Feb 19, 1992 1:23 PM
It's good business sense for Intel. When they test 486DX parts, those that fail the coprocessor tests get labeled as 486SX. Essentially, Intel is selling scrap.
#9441From: Jay Parisi [Anim/Gra TM]Feb 19, 1992 3:30 PM
That just makes it sound even worse, if part of the chip is "bad" already, how long does the rest of it have? Jay
#9519From: Evan Yares [WeirdTM]Feb 20, 1992 3:25 PM
Fortunately, silicon is pretty stable. 486SX chips should last as long as 486DX chips. It's the same problem with hard disk drives. At least in that case, a bad sector can be flagged out.
#9520From: Larry MintonFeb 20, 1992 3:26 PM
If there was a flaw on the substrate under the math coprocessor, and the CPU side tested OK, you shouldn't have any more than the normal failure rate on the CPU side.
#9634From: Terry GilbertFeb 22, 1992 4:32 PM
Jay, This is the world of marketting not engineering. The 486SX only "did" something worth money until you bought the 487SX. After that it has no use and cannot be wasted. It no longer has any real value. As to why Intel brought out the 486SX, This allows Intel to reduce the price on SOME 486s to compete with AMD without lowering the price on ALL the 486s. This way they can maintain market share with some systems and still maintain profits on the others. "It ain't pretty but it works"