Windows 7 - BIOS Setup always show in turning on a Notebook/Laptop

Hello, i'm a newbie in troubleshooting, I have a problem when I open my notebook/laptop it always show the BIOS Setup, so what i do is I press "ESC" on keyboard the select "Yes" to discard the changes in BIOS and it loads the windows and works properly I tried to restart but when I restart same process the BIOS Setup always appear, how can I prevent the BIOS Setup showing in turning on my notebook/laptop?

I did recently;
-Startup Repair; but doesn't solve the issue.
-I disassemble my notebook/laptop I thought it has a CMOS battery
-Load Default Settings of BIOS; still doesn't change anything.

Sometimes the BIOS Setup doesn't appear in starting up but it shows a message that something like there's a problem in BIOS, I forgot the exact message then below there's a choice:
Press F1 to run Setup.
Press F2 to load defaults.................etc.

Pressing F1 it goes me to BIOS Setup
Pressing F2 the windows loads normally

It does sound like a failing (or failed) CMOS battery. Is the BIOS clock/date resetting itself to the same time/date? What is the make and full model number of the laptop/notebook?

ASUS Eee PC 1005HAB

I open again my notebook here's the exact message and scenario;

This is the post message:

CPU : Intel(R) ATOM(TM) CPU N270 @ 1.60GHz
Speed : 1.60 GHz

Press ESC for BBS POPUP
Press F9 for image recovery
Press ALT+F2 to execute ASUS EZ Flash
DDRII -533/CL4, Single-Channel Mode
Initializing USB Controllers .. Done.
1016MB OK (Installed Memory Size:1024MB)

Auto-Detecting Pri Master..IDE Hard Disk
Pri Master: ST9160314AS 0002SDM1
Ultra DMA Mode-5, S.M.A.R.T. Capable and Status OK
Auto-derecting USB Mass Storage Devices ..
00 USB mass storage devices found and configured.

Please enter setup to recover BIOS setting
Press F1 to Run Setup
Press F2 to load default values and continue

then I press F2, the Windows Boot Manager appear I select Windows 7 and my notebook open the system date and time are correct it not reset to its factory setting.

then I restart my notebook and here's the problem instead of showing the post message above it shows/directly go to BIOS Setup Utility, but the time and date are still updated so I exit choose "Exit and save changes" even though I didn't change anything, my notebook restart then again it directly go to BIOS Setup Utility, then I try to Exit but now I choose "Exit and discard changes" then bang.... the windows loads it seems that everytime I choose/save changes in BIOS the windows doesn't load it always go to BIOS Setup but everytime I choose "discard changes" the windows load what do you think is the possible problem of my notebook?

Welcome to Seven Forums Paul, when did this problem first appear?
Have you added new software or harware?

I don't know when did this first happen since I left my notebook in my cousins house but yes there's new software installed, you think that's one reason?

What is the BIOS version on your ASUS??Try to check in ASUS website if there is new BIOS version available for your model number.Flashing to newer version (if available) of BIOS might solve the problem.

here's the version of my BIOS v02.58

From what i found out on ASUS support website,the latest BIOS version for your laptop model number is BIOS version 1601 release date 14/07/2011.Here is the link ASUSTeK Computer Inc. -Support- Drivers and Download Eee PC 1005HAB

It would be better if you can post a screenshot of your BIOS with version number visible.Flashing BIOS with version not for your laptop can render your laptop inoperable.Take utmost care while flashing BIOS.Make sure laptop is plugged in and battery is full just in case.

sorry i posted a wrong one here;
BIOS version: American Megatrends Inc. 0801, 8/26/2009
SMBIOS Version: 2.5

I downloaded the updated BIOS version how can i install/update my BIOS?

Your BIOS version seems a bit outdated.I couldn't find the latest version from AMD website nor from ASUS website.
On the bottom cover of your laptop is the product serial number.Here is how you can find it ASUSTeK Computer Inc. -Support- Repair Information

Then visit the ASUS support page i listed above and type in your product serial number and check if you can find the latest version of your BIOS.

Re-flashing to the latest version might solve your problem.