Thanks a million for your time.
Have opened the machine up and very supprised at the way it was done 20 years ago. A battery on the floppy controller card.
Could not find what looked like a cpu anywhere just a set of switches 1 to 8 on the mother board which I suppose is for the speed setting.
Here is what I found inside.
(1) 8 card slots. Too short for ISA. What was the bus then.
(2) Bios chip ERSO/DTK 1986 2380 I presume the 2380 is version 2.38. Version 2.42 comes up on screen so I must have had a bios upgrade ??
(3) ON motherboard
    (a) Sticker Imageering 32427
    (b) 10 mhz turbo board
    (c) 811070  
    (d) DTK 048873 PIM-TB19-2 Rev 9 
    (e) S/N A022271
(3) Video Card Color Graphics Printer DTK PII-153 1987
(4) Floppy Card GW202. The 2032 battery sure has been around for years.
(4) HDD card Elmec 8001 Seagate ST11R SL04
(5) Hard drive Seagate ST-251-1 41 mbwith a sticker giving
       Cyl      Hd     BFI
        29      3       2123   
        48      3       2131  
        49      3       2129
        63      3       2136
        313     3       4949
        457     4       8039 
How do you get into bios to see HDD settings. What is BFI. Could find nothing on Seagate site. 
(6) 5.25" Floppy drive is TEAC 15532064-00a What size disc does it take as could not format 360 or 1200.
(7) power supply is 150w 
On boot up the screen shows 
DTK Corp
DTK/ERSO/BIOS 2.42 1986
RAM TEST..  640k
SEAGATE ST11 Bios Rev 2.0.0
Drive C is at ST251    There is no reference to CPU. Suppose bios will disclose this.
Searching web cannot figure who it was made by Nan Tan or Kopok or Clevo. Is the Imagneering Australian site the original importers who look like they have discontinued selling PC's.
With DOS 4 floppies I partitioned HD, formatted it, labelled it and ran CHKDSK /F and all is okay but every time I try and install DOS I get to the third disk of the five disk set and I keep getting " An error occurred while installing DOS "
Doing dir on C: there are strange looking files(a symbol with long numbers) at the root.
Is this norn\mal for the root sector 1 files of DOS 4 ? 
I can create and delete fdirectories on C:.
I can copy file to and delete files on C:.
C: drive appears to be okay.
I can read my 5 DOS 5 floppy set via dir on the machine so presume 5.25" DOS 4 set okay.
Did a A> sys C: and files were copied to C: but were those strange looking files again ie a symbol with long numbers.
My main interest at this time is 
(I)   Any resourses on web as to mother board manuals etc.
(II)  How to get into bios.
(III) Any secret to installing DOS 4
(IV)  Any tips to know about machine.

Sorry to be so long winded but I gather you need to know all details of machine to identify what I have.
I hope I have not voided the warranty by taking off the lid. After all there were no warning stickers.
Love the green. Sure is a talking point.

Regards
Basil