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Re: Transwarp upgrades

Ben:
I usually purchase crystals from digikey.  Keep in mind that minimum
order of $25 is required to avoid a $5 handling fee.  Usually I spend in
excess of $25 so it's not an issue.

As far as opinions upgrading wihtout replacing the CPU chip, the
following has been learned from trial and error.  Of your CPU chip has a
'-6', it will probably run at 7-7.5MHz (28-30 crystal).  If you have a
'-7', it will probably run 8-9MHz (32-36 crystal).  If there is no dash
number on the chip, they seem stable at 10-11MHz (40-44 crystal).  Keep
in in mind that anything above 8-8.5MHz may cause your cache ram to
become the weak link, even if the CPU can handle it.

I put a socket on my TWGS just so I could use either size crystal, so I
buy 1/2 size for either a Zip or TW accelerator.  Just make sure you put
the crystal in correctly or !piff!.  :{  Although >I've< never done
that... especially with my LAST crystal of appropriate frequency, nope,
never.  In other words buy a few extra.  (Better to get a couple exta
crystals than pay the $5 fee.)

Thankx,
Ed

Here is the list from DigiKey's Catalog of compatible 1/2 size crystals.
(As of 10/2000 anyway.)

Page 289, Epson Brand, Looks like a DIP with 8 pin package, much better
selection of frequencies
32MHz (8)	SE1111-ND
33.333MHz (8.3)	SE1115-ND
36MHz (9)	SE1116-ND
38MHz (9.5)	SE1117-ND
40MHz (10)	SE1118-ND
42MHz (10.5)	SE1119-ND
44.9MHz (11.2)	SE1120-ND
46MHz (11.5)	SE1121-ND
48MHz (12)	SE1122-ND
50MHz (12.5)	SE1123-ND
55MHz (13.75)	SE1124-ND
60MHz (15)	SE1125-ND
64MHz (16)	SE1126-ND

Page 295, CTS brand crystals in 1/2 size 'can'
32MHz  (8)	CTX174-ND
40MHz  (10)	CTX175-ND
50MHz  (12.5)	CTX176-ND
64MHz (16)	CTX177-ND

Page 301, ECS brand crystals in 1/2 size 'can'
32MHz  (8)	XC254-ND
35MHz  (8.75)	XC255-ND
40MHz  (10)	X225-ND
48MHz (12)	XC256-ND
50MHz (12.5)	X226-ND
64MHz (16)	XC257-ND

Ben Zotto wrote:
> So I'd like to do something with it, and it seems a straight speed
> upgrade is best.  (Opinions on this welcome).  I figure without
> getting a new chip from WDC I can probably try a 32Mhz oscillator
> or even a 36Mhz one?  Can anyone offer an opinion on this, or
> tell me where a good place to find such oscillators is?