286 Express Card Speeds

[Great Hierophant]

I recently acquired a Tandy 1000 SX, and along with it I got a 286 Express Card. This is an excellent card to have. Unlike some other accelerators, it allows you to use your existing 8088 & 8087 in addition to the 80286 on the card (and 80287 which can also be added). In fact, unless you load its device driver or program, it does nothing.

The system will boot up with the 8088 by default with the card installed. The 1000 SX allows two speeds without it, 4.77MHz and 7.16MHz. The 286 Express card does not care which speed is selected when it is activated. Commands like MODE SLOW and MODE FAST do not affect this card when activated. However, because the 286 has a 16-bit data path and the RAM in an SX is 8-bit, the card also has 8KB of cache to improve performance. The cache can be disabled.

With the cache enabled, the system is almost as fast as an IBM AT. With the cache disabled, the system is only a little faster than the stock Tandy 1000 at 7.16MHz. Therefore, you gain not one, but two new speeds when you insert this card into your 1000 SX.

 

[Great Hierophant]

Here are the speeds of each option, as tested with MIPS 1.20:

(IBM PC @ 4.77MHz 8088 = 1.00 for all tests)

4.77MHz 8088
General Instructions = 0.97
Integer Instructions = 0.98
Memory to Memory = 1.01
Register to Register = 1.00
Register to Memory = 1.01
Overall Performance = 0.99

7.16MHz 8088
General Instructions = 1.24
Integer Instructions = 1.38
Memory to Memory = 1.29
Register to Register = 1.39
Register to Memory = 1.27
Overall Performance = 1.29

286 Cache Off
General Instructions = 1.27
Integer Instructions = 2.08
Memory to Memory = 1.00
Register to Register = 2.68
Register to Memory = 0.99
Overall Performance = 1.37

286 Cache On
General Instructions = 3.31
Integer Instructions = 6.11
Memory to Memory = 2.63
Register to Register = 7.14
Register to Memory = 2.94
Overall Performance = 3.76

 

[gerrydoire]

Intel 386 Card

Intel 386 Card

I'd love to get my hands on a Intel 386 Card for the 8 bit slot, Inport i think it's called, see how that performs

 

[carlsson]

Google and Wikipedia suggests Intel Inboard. So you were close, but no cigar. See also Microsoft for advice on whether you can run Windows on it. Of course it has been discussed on this forum as well. :-D

 

[Chromedome45]

The Intel InBoard 386 required it's own special version of Windows 3.0 to run properly. And BTW Nice find with that SX and 286 card. I'm Jealous

 

[Great Hierophant]

I do not know if the Tandy 1000/A/HD will post the same results because I don't have one. I suspect it probably will, and with the cache off you have the rough equilavent of the 7.16 speed of the EX/HX and SX. I would appreciate if someone shared the results of one of those machines with me.

 

[per]

I recently acquired a Tandy 1000 SX, and along with it I got a 286 Express Card. This is an excellent card to have. Unlike some other accelerators, it allows you to use your existing 8088 & 8087 in addition to the 80286 on the card (and 80287 which can also be added). In fact, unless you load its device driver or program, it does nothing.

The system will boot up with the 8088 by default with the card installed. The 1000 SX allows two speeds without it, 4.77MHz and 7.16MHz. The 286 Express card does not care which speed is selected when it is activated. Commands like MODE SLOW and MODE FAST do not affect this card when activated. However, because the 286 has a 16-bit data path and the RAM in an SX is 8-bit, the card also has 8KB of cache to improve performance. The cache can be disabled.

With the cache enabled, the system is almost as fast as an IBM AT. With the cache disabled, the system is only a little faster than the stock Tandy 1000 at 7.16MHz. Therefore, you gain not one, but two new speeds when you insert this card into your 1000 SX.

I got a kindof similar card for the XT, but it got it's own (70ns!!! Problably 16-bit) RAM onboard. Do you have any pictures of your card?

 

[Cloudschatze]

Do you have any pictures of your card?

<cough> http://www.vintage-computer.com/vcforum/showpost.php?p=107692&postcount=1 </cough>

 

[IBM Portable PC]

I've just purchased an "Express Card" (Tandy catalog number 25-1035), however it only has the daughterboard for the 1000A and several other models, NOT including the original 1000 for which a different daughterboard was required (PC Technologies part No: AXX - 7130).

Does anyone have one laying around that they don't need etc?

Does anyone know what the precise differences are so that I can modify the one that I have?

 

[Great Hierophant]

I think replacing the 1000's motherboard with a 1000A's motherboard would be a better option to get the card working in your system.

I've just purchased an "Express Card" (Tandy catalog number 25-1035), however it only has the daughterboard for the 1000A and several other models, NOT including the original 1000 for which a different daughterboard was required (PC Technologies part No: AXX - 7130).

Does anyone have one laying around that they don't need etc?

Does anyone know what the precise differences are so that I can modify the one that I have?

 

[IBM Portable PC]

I just installed an Express card in my 1000A and it works fine, however it does not appear to work with a V20 CPU, only an 8088?

No surprise, obviously the firmware looks for a specific CPU identifier and fails when it cannot see the usual 8088 response.

Pity though...........