Strange 64 problem

[m_silkstone]

I'm currently (trying to) running vista 64 (sp1) on my comp (E2180, Asus p5k-vm, 2gb ram, HD4850).
I just tried to install 4 more gb of 1066 memery but it kept crashing on startup/boot. now i've taken it out Vista won't boot (even with reduced memory timings) the screen goes black before the login screen but i can move my mouse cursor so it hasn't crashed!
I've tried using system restore but it said there was an error on my drive and to run checkdisk. I tried to run check disk and i got a notification that it would run on next boot. Re-booted, no checkdisk, same problem.
I also tried to run startup repair from the installation disk, but the same thing happens!! - before i get to the setup screen the screen stays black, i can still move the cursor, however. Any ideas what this could be???
The only thing that works is safemode (can still use networking).

 

[badge]

Use one DIMM of RAM in slot 1 only. Boot into BIOS and set memory voltage to 2.1v. After you get back in to windows, reinstall the remainder of the RAM. You should run memtest to be sure your PC28500 DIMMS are not faulty.

 

[m_silkstone]

thanks badge. I've run mem test, says everything is fine. i reduced the current memory settings to 800 6-6-6 anyway, just to be sure (auto voltage).
The new dimms are in the box awaiting return tomorrow.
I've run chkdsk and it's come up with multiple errors. i believe this is the problem, but i have no way of for chkdisk to repair the files (read-only mode)
I've tried doing everything mentioned here: http://www.vistax64.com/tutorials/67612-check-disk-chkdsk.html
but to no avail
I don't have a floppy drive and the Install CD won't boot!
How can i check my disk

 

[badge]

Auto voltage is 1.8v. PC28500 requires 2.1v.

 

[m_silkstone]

just tried in 2.1v. same problem apart from in safe mode. Auto volt worked before anyway.
Really wierd as the install CD won't load. i'll try a backup install CD see if that is any better

 

[pat mcgroin]

chkdsk /f will fix problems
chkdsk /? for help with different switches

 

[m_silkstone]

I couldn't run chkdsk and the vista installation CD wouldn't run!
I managed to fix it tho, i dug up my old xp cd and used the recovery console to run scandisk. back to working order now.
Thanks for the replies, i think i better make a recovery disk now in case it ever happens again.