I bought 320gb hard disk thinking that it will work with Asrock P4VM800 motherboard.In windows 320gb hard disk shows as 137gb.So i flashed the bios and after doing that i get the message at startup saying cmos checksum bad. press f1 to enter setup and f2 to load default values and continue.I want to remove this error and make it accept the 320gb. Any ideas?

SP2(service pack2) should be preloaded with you're OS cd to fix this issue, reformat you're drive with SP2 on you're XP disc and you'll be able to recodnise past 137GB.

Alternate Solution: Using "Partition Magic" resize the partition, SP2 will need to be installed and you can DL it off Microsoft's Webby.

Hi there,

For the HDD issue, Windows XP does not see HDDs over 120 GB (aka 137 GB), but there is a simple patch to solve this issue, available on your hard disk drive manufacturer website.

For the setup issue, press F1, re-configure setup and exit, choosing "save and exit". If the problem persists this means that you battery must be replaced: http://www.hardwaresecrets.com/article/81

Cheers,
Gabriel.

Of course my solution is only to see past 137GB on you're drive(I had the same issue awhile back and SP2 preloaded CDs cure this issue along with you're BIOS being updated enough to be able recodnise the storage space)

As far as checksum errors go:

Some peripheral devices and expansion cards contain executable code stored in a ROM. The ROM has a checksum value in it that is used as a double-check by the BIOS to ensure that the code has not been corrupted before the BIOS tries to use the device. This error message is generated when the BIOS detects a mismatch between the stored checksum value and the one it calculated at boot time by looking at the expansion peripheral's ROM code. A four-digit address may be included in the message to indicate the address of the failed peripheral. Resetting you're battery may help set you're BIOS back to normal but in many cases this may not work if a BIOS was inproperly flashed.

Reset you're battery and pray, Good Luck.