I'd like to get my old hp pavilion 7855 running again.

The original harddrive had a black screen saying something along the lines of 'no hard disk'

I got a harddrive from someone on craigslist. I'm not sure if its been formated or anything but when I put it in the computer, the HP screen comes up, then it goes to a black screen and says 'no operation system detected'.

I've been trying to find help on google, i've tried putting the reboot disk that came with the computer in and restarting the computer. I can't seem to access the bios, whenever i push a key on the keyboard it just repeats the phrase 'no os detected'


Any ideas? my brother took the cd rom drive out a while ago to use for his computer, so I put the disk in the 2nd drive (cd-rw)

Detecting BIOS has nothing to do with operating system.
When the computer turns on, look at the bottom of the screen.
You should see something like:
<some key> setup
Pressing that key should enter BIOS area.

the screen says:

no operation system detected
_



Nothing else.

any key i press just creates another line saying the same thing, no operation system detected _
I figured if I could get into the bios i could try to change something or force it to use the reboot disc.

HP logo screen doesn't load at all?

Is you cd-drive set up as the primary master? If the jumpers at the back of the drive & check it's position against the diagram on the drive. There might also be a arrow pointing to the master pins. Also make sure that the cable it is connect to is NOT the same as the one connected to the hard drive if you have more than one. In addition you need to go into the BIOS & change the boot order so that the cd-rom is highest on the list.

Yes...the hp logo screen loads before the black screen appears and says 'no operation system detected _'

There are 2 sets of wires. Both have 3 connections on them. 1 connected to the mobo, 1 says slave the other says master.

I have the slave connected to the harddrive, which is set to slave. and the master is connected to the cd drive


I just figured out I can enter the bios through the HP screen.
I went in, adjusted the boot line up so the cd drive is on top. But it still says the same thing, no operating system detected.
I also tried putting the harddrive at the top, says the same thing.

any other ideas?

I went in, adjusted the boot line up so the cd drive is on top. But it still says the same thing, no operating system detected.

With CD in, after restart, do you see this message?
Press any key to boot from CD
If not, either CD is bad, or CD drive is bad.
What exact CD do you use?

the cd is called "hp pavilion home pc system recovery"

With CD in, after restart, do you see this message?
Press any key to boot from CD
If not, either CD is bad, or CD drive is bad.

...

Well this won't help in your case but the HDD should be primary master and the disk drive should be secondary master. Have you gone into the BIOS to make sure that. If you have an external drive or a USB drive large enough you could try & copy the installation files to either and install from that I would remove everything else from that drive. Also through newegg a new optical drive shouldn't cost you more than $20 for a DVD-rom or $50 for a burner.