Well I emailed tech support and I got it working. I've made a tutorial, including the neccesary files. Any suggestions etc are welcome:
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Making your MS-7310 boot with 2x two Gigabytes of memory inserted.
(The first section is for creating a bootable usb disk.)
===Section 1===
1. Download Unetbootin from http://lubi.sourceforge.net/unetbootin.html
2. Insert a USB drive and run the program. Click "== Select Distribution ==" and select FreeDOS
3. At the bottom select your USB-drive and click OK.
===Section 2===
4. Copy the included files to the USB drive. I suggest you put them in a folder called "bios". (You could also put the files on a floppy disk if you prefer)
===Section 3===
5. With the USB drive inserted, reboot your pc (you could also use a floppy, search the internet for this).
6. At booting press del to enter setup, and make sure that your pc is set to boot from USB first!
I. Advanced BIOS Features
II. Boot sequence
III. Removable Drives
IV. 1st Drive USB
V. 1st Boot device should be USB drive now.
7. Save and exit setup. The pc will now reboot.
===Section 4===
(IF YOU DON'T KNOW WHAT YOU ARE DOING, THIS IS THE TIME TO STOP)
8. Assuming you have just completed step 6, the pc will now boot from your USB drive.
9. Select "FreeDOS Live CD with HIMEM + EMM386".
10. Once in FreeDOS, go to your USB drive (presumably B:) by typing:
B:
11. Now type: "dir" and you should see the contents of the drive listed. If you don't, try other
drive letters (A: C: D: etc), until you do see the contents.
12. Type: "cd bios"
13. Type: afud412 a7310nms.191
14. Sit and wait until it's done. DO NOT RESET, REBOOT OR INTERRUPT POWER, YOUR SYSTEM WILL NO LONGER FUNCION IF YOU DO!
15. When it's done, reboot your system and press del to go to setup again. Now select load optimized defaults, and
save and exit.
16. Turn of your PC, insert the memory and reboot.
17. Your system should now boot properly with 4GB inserted. (Mind you, you do need a 64-bit OS to use all of it.)
Note: This guide comes with no warrantee whatsoever, you are responsible for any damage to your system.
This guide was written by Pim a.k.a. OmnificienT
v1.0
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The attachment contains this little tutorial and the neccesary files.