PDA

View Full Version : Orchid TurboEGA acquisition, need help



username1
July 26th, 2017, 07:07 PM
Hello everyone, so I just recently got this cool old graphics card, a turbo EGA by orchid. From what I've worked out it's also an accelerator card for IBM PCs and such, but I'm clueless beyond that and haven't found much info googling. My.maim questions are of functional use. How would I get it going in an actual PC? There are four small switches and a toggle on the end, how do I position them? Theres a 40-pin cable coming off a chip socket, where does it go? And what exactly do the RCA jacks do on the card? Sorry if I come across as not knowledgeable, this definitely isn't my area of expertise and I haven't found the answers to this. I'll attach photos of the card and any knowledge or anwsers would be fantastic, thanks.
http://i.imgur.com/OYykVob.jpg
http://i.imgur.com/1Ulg0ZR.jpg
http://i.imgur.com/aLdfEyq.jpg
http://i.imgur.com/gvtm5vz.jpg

modem7
July 29th, 2017, 03:54 PM
So this is a continuation of your thread on the card at [here (http://www.vcfed.org/forum/showthread.php?58039-can-anyone-help-me-identify-the-missing-chip-on-my-TurboEGA-card)].

Without concrete information, such as a user manual, partial answers come from sources such as the magazine article at [here (https://books.google.com.au/books?id=LRBokcwLB70C&pg=PA324&lpg=PA324&dq=Orchid+Turbo+EGA&source=bl&ots=LgfScMh144&sig=pO-iY_IiWhNOC2fEmDQJ46Yu6ns&hl=en&sa=X&ved=0ahUKEwj74Y6S1JnUAhWKoJQKHYYTBS4Q6AEIMDAD#v=on epage&q=Orchid%20Turbo%20EGA&f=false)].


There's a 40-pin cable coming off a chip socket, where does it go?
This is part of the 'accelerator' functionality. You remove the 8088 CPU chip on your motherboard, then plug the cable end into the now-empty CPU socket.


And what exactly do the RCA jacks do on the card?
If (repeat: if) Orchid have copied the IBM EGA card, then the jacks are part of the 'feature connector' functionality, per the diagram at [here (http://minuszerodegrees.net/video/ibm_ega_card_feature_connector.jpg)].
That is strengthened by the, ".. are two RCA phono jacks for special EGA features (not composite video) ...", that appears in the aforementioned magazine article.
Specialist use only. Research 'feature connector' for more information.


There are four small switches and a toggle on the end, how do I position them?
As for the four switches, the aforementioned magazine article indicates that, like most other EGA cards, the switches are set according to the type of monitor that is attached.
If (repeat: if) Orchid have copied the IBM EGA card, then the settings are per [here (http://minuszerodegrees.net/ibm_ega/ibm_ega_switch_settings.htm)].
Maybe the current setting (all off) means 'auto'. That is a guess.

The toggle switch is described in the same magazine article (paragraph starting with, "A toggle switch on the bracket ...").


How would I get it going in an actual PC?
I suggest that you use the 'EGA card' functionality first, then when that is working, try the accelerator functionality (remove the 8088 CPU then plug in the cable).

For 'EGA card' functionality:
1. Remove existing video card in your IBM 5150
2. Set 5150 motherboard switches to the EGA setting
3. Set TurboEGA card switches to suit EGA monitor <------- 'tricky' without authoritative information
4. Add TurboEGA card to 5150
5. Attach EGA monitor to TurboEGA card