Did you clear the event log and load the BIOS default settings after you updated the BIOS? If not, I'd recommend doing so.
If the problem continues, let me know the following, please:
1. The previous BIOS version you indicate that doesn't exhibit the problem:
2. The latest BIOS version you tried with:
3. The Altered Assembly Number (AA #) of your particular Intel(R) Desktop Board DH55HC:
Note: The AA# is located on a white sticker, right on the board itself (see http://tinyurl.com/6j8nbf). If your board is able to boot into BIOS, at least, you can also have access to it in BIOS [Additional System Information under the Main menu; (see http://tinyurl.com/m2updf)].
4. Just to be in sync, what do you mean by "cascades like a waterfall"?
I loaded the bios via the exe, i think defaults were set automatically as i use the AHCI set-up and IDE was set when i checked.
Which event log? in system tools?
By waterfall i mean as if the picture has turned to liquid and just runs down the screen... hard to explain any better really.
I reloaded Bios TCIBX10H.86A.0028.EB.EXE, please note i only loaded a new bios as occasionally on wake from sleep i sometimes get a "not enough video memory to run windows 7" fault. However this is only rare and i'm loathe to try another bios now...
Ok cheers i may give this a try again some time when the wife doesn't need to watch big brother....