PC won't boot up.. black screen.. bought recovery CD but no help.. PLS HELP!!!

[42n8]

When I start the computer it first shows the Dell logo then goes to a black screen with the following: Primary drive not found... Alert! OS Instal Mode Enabled. Amount of available memory limited to 256MB. Strike the F1 ket to continue, F2 to run the setup utility.
It is a Dell OptiPlex GX270 with 1Mb ram and 240HD with Windows Vista Home Edition installed which was an upgrade from factory installed Windows XP. I do not have the Windows XP CD.
When I strike F1 it says... strike F1 to retry reboot, F2 for setup utility.
When I strike the F1 again and it repeats the above. etc. etc.
I purchased a program called 'the Emergency System Recovery Boot CD 4.X" but when it is booted up with the CD and strike the F1 key it says: boot: cannot read Master Boot Record. Boot: When I press Enter it goes to a blue screen for the Ultimate Boot CD V4.1.1 with the following choices:
Mainboard Tools
Hard Disk Tools
Filesystem Tools
Other Tools
User-defined Tools
DOS/Linux Boot Disks
*Boot First Hard Disk
*Boot Second Hard Disk

Please Help! I do not know what to do from here.

[Geek-9pm]

The clue is "Primary drive not found." 
Your Hard Disk drive is not working at all. Your CD drive is working. So that makes me think the the power connector to the Hard Drive came loose. I have had that happen a lot. You have to unplug the computer and  open the case and inspect the power cable going to the Hard drive. It has a red, yellow and two black wires.Wiggle it a bit lto see if it is loose. Make sure it is all the way in. If it comes out, be sure to put in in the same way. I think the yellow wire is closer to the side. And there is a chance that it is the flat ribbon cable that came loose from either end. Again, be careful how you push in in. Maybe that was it!

[Broni]

According to: http://pompone.cs.ucsb.edu/admin/530_Workstation/2codes.htm

Alert! OS Install Mode enabled. Amount of available memory limited to 256 MB.

Cause
The  OS Install Mode option in system setup is set to On. This limits the amount of available memory to 256 MB because some OSs will not complete installation with more than 2 GB of system memory.

Action
After the OS is installed, enter system setup and set the  OS Install Mode option to Off.

P. S.
1. Why didn't you perform upgrade from XP, not clean install?
2. With Vista, add an extra 1GB of RAM.

[42n8]

To Broni:

Thank you for your assistance.
I did reset the OS Install Mode to OFF but still the same occurs.
(By the way, I had installed Vista as upgrade from factory installed XP.)

By inserting the recovery CD I can get to a blue screen with the following:
..
CPU Tests
Memory Tests
Peripherals Tools
CPU Information
System Information
Benchmark Tools
BIOS Tools

Can you help?

[Broni]

I assume, you have Vista CD?
Was Vista install, clean install, or upgrade from XP?

[42n8]

It was an upgrade from XP.

[Broni]

I assume, you have Vista CD?

[42n8]

yes I do

[42n8]

I have tried booting up with the Vista CD but it will not allow it.

[Broni]

Is the boot order in BIOS set to CD first (or second, if you have floppy drive)?

[42n8]

Here is what it shows in Boot Sequence:

(checked) 1. IDE CD-ROM device
                2.  Hard Disk Drive (not installed)
                3. Integrated NIC
                4. Floppy device (not installed)
 

[42n8]

I now get the following message:

Memory address line failure at 33EFBAE8, read 10100010 expecting 10101010
Decreasing available memory
The amount of system memory has changed.
Primary hard disk 0 failure
Strike the F1 key to continue, F2 to run the setup utility

[Broni]

First of all, disable boot from Integrated NIC.
When you start computer with Vista CD in, are you getting "Press any key to boot from CD" message, at some point?

[42n8]

No message like that with Vista CD in.

[Broni]

Do you know, if CD drive is in working condition?

Run memtest: http://www.techspot.com/vb/topic62524.html