🚀 go-pugleaf

I am seriously thinking about getting a high-end 486 system; however, the Local Bus
hype has me a little worried. Many reviewers regard it as the best thing since sliced bread,
but many competent dealers I have talked to told me to stay away from Local Bus sytems at this point in time,
even though they  are selling such systems themselves. The so called VESA Standard seems
to contain a lot of lose ends (and few people have actually seen the specs).

Here is my concrete question. I have heard the VESA Standard specifies the clock to be max. 40Mhz.
On the other hand a lot of machines are advertised as true  (486DX-50) 50Mhz machines with
VESA Local Bus. Do they just run the Local Bus at a higher than spec frequency, or do they half the clock?
Many of the big mailorder houses  sell 486DX-33 or 486DX2-66 machines with Local Bus, but no 486DX-50.
Is the potential incompatibility at 50Mhz the reason they don't offer such systems? 
Anybody out there who knows what's going on?

Joachim

P.S.: No flames if this has already been discused. I am new to the group.