Try to 2.9.43 on an IDE drive: I have burned 4 different CDs… none boot on any computer in my data center. Ok, try PXE boot, no PXE capable cards want to talk to the Mikrotok Netinstall. Tried 4 diferent ones. Made a boot floppy in Netinstall and it does not boot… several other do not boot, on any machine with a floppy drive. I have built 3 dozen Mikrotik routers and APs. This sucks completely. 
In my language we say: “when trouble comes, open your door…” meaning that trouble never come one at a time.
Try with only one computer installing through floppy and netinstall. Check the bios settings for boot device priority. Check the floppy disk you have maked. Don’t try with different floppys, different computers and different methods all in once cause you may never find the problem (cause they maybe many)..
frustrated i take it : ) using floppies that are more than a week old seem to cause that around my house too … and drives that are aligned differently than each other.
No see, I tried ALL methods multiple times with the one machine I need to install to. When all failed muliple times I try and find a machine that will boot ANY WAY. to put the target drive into. Nothing works. Perhaps it is the beta Netinstall that comes for 2.9.43?
aaaiiiiii, finally find a machine that knows how to PXE boot competantly. yay. Odd… rb153 does not pxe boot.
Really though, This should be better reliable.
Kiira
Maybe. I havent tried it..
Try 3beta. it works fine cause i just used it.
I use a IDE to USB interface for the hard drives then Netinstall to it…
GotNet, does it really work…it would be a great news..
Yep, same deal for the WRAP boards with compact flash drives. Only issue might be a change in drive geometry in an older motherboard.
What is GotNet? I finally found one machine, a high end dell serever, that would PXE boot properly. Naturally it’s at the bottom of a rack. 
I’m curious why Mikrotik cannt make a bootable CD like every other linux distributer in the word. Using shoelace and editing the boot partition in hex was easier than this. h aha
Also rb154 does notr netboot. It should.
Kiira
I’m an ISP and I GotNet. Plate on my 1964 Corvair Monza 900 convertable too. That one gets a lot of questions at the car shows.
Have you ever looked in download section?
http://www.mikrotik.com/download.html
There are available ISO image. Download and burn to disk.
The isolinux disk did not boot on any machine. it froze sometime after the banner. I burn ubuntu disks on this burner and they never fail.
i’m very familiar with ISo CD images too, but i find the choice of Netinstall very easy and great, so you don’t spend a bunch of cds only for beta testing..
I just ran into major problems with the current netinstall on the download site. Netinstall beta7 does not show any remote clients, whereas running netinstall v2.9.40 works perfectly. This is on an intel 815EEA2 board using the onboard intel 10/100. I cant PXE, but booting from floppy works fine with the 2.9.40 netinstall.
Sam
Try to install an earlier version of ROS from a Booteable CD, and then upgrade to 2.9.43, It works fine for me, I guess I did it from 2.9.42 and work OK.
Regards. 
If it’s THAT hard, get the hard-disk out, put it on any other machine you want, install the routeros, and put it back.
It’s really that simple.
I used machines with no floppy and no cd-rom, and the easiest way to install it was to have the router already installed on hdd, on another machine.