In another forum I get someone who says "I thought you could put 2 more ram modules in the mainboard and run four modules in dual channel mode..."

So, I think, "No Way" and I go to my mainboard manual which says "sure..... go for it as long as the ram total amount is equal on both channels".

I put the ram in and I got a noboot into windows, froze on a black screen. Reboot - keyboard error, Blue Screen of Death on windows load. Check BIOS set defaults, reboot - got a screen I NEVER saw before, keyboard error, DVDROM not recognised at all.

I took the ram out. Reboot, still no DVDROM, change the DVDROM over to secondary IDE as slave, it works fine. So, I destroyed the I/O chip on my mainboard by expanding ram beyond 1 gb.

I ring up for warranty on my mainboard, and I'm about to order a replacement because I ain't waiting for warranty work...... uhuuuh, no way.

I decided to Flash BIOS as a last resort. (I tried everything else!) and VOILA! I got my Primary IDE slave link back. So my new mainboard is fine...... Whew!

I boot into windows and there are now error messages, eminating from a now disfunctional firewall. I try to uninstall the firewall, no go. Tried to delete registry keys to firewall....... no luck, darn thing protected itself.

Format.

Well, my FS9 is running a lot faster on a clean install now!

I have absolutely no idea what just happened to me today, perhaps someone could shed some light?

The only thing I was thinking, was that the new additional ram was single sided modules and the older stuff is double sided, other than that, both work fine on the board seperately.

If someone told me adding ram would corrupt BIOS and wipe out my firewall, (and consequently lock me out of internet security) and cause me to re-install the op sys,  I would have said they were nuts, but hey..... I'm still learning.

Or may be the moral is, do not experiment on your own gear if somebody says "...I thought............"

On the other hand no risk no learn.

Lucky you know what you are doing & came out of it alive.                                luke

Running two different kinds of RAM modules in dual channel (double vs single sided) will get you in some serious crap.

In dual channel, all memory modules MUST be the same. No exceptions.

Here's the weird part, the computer should have booted to post and gave you an error during memory check. Remove the memory and it should have booted fine. Why it screwed with your IDE controllers and windows setup is strange.

And you can put four modules (or more) in dual channel. I'm doing that right now. The thing is though, all my ram modules are exactly the same and I put those in there before installed windows.