I too am having a difficult time with the EVGA GTX 460.  Every component of my computer is brand new:

Motherboard: ASUS M489GTD Pro
Processor: AMD Phenom II x4 965
G Skill Ripjaw 2GBx2 RAM
Corsair TX750w Power supply
Windows 7 64bit

However, I have not had the login screen problem.  Instead I am experiencing freezing then to the blue screen.  The freezing takes anywhere from a few seconds to a minute and the blue screen ranges in different lengths as well. This only happens when I am playing either Starcraft II or World of Warcraft. I cannot tell if any particular thing is causing this problem.  Drivers and BIOS are updated. A friend of mine and I couldn't figure it out after we suspected a bad stick of RAM, which was not the case.  I googled my problem but came across yours which is somewhat similar. I hope I don't have to RMA this thing.

I got my replacement and I haven't had any problems yet, although its only been two days. 

I have a similar problem =(  ( http://forums.evga.com/tm.aspx?high=&m=528413&mpage=1#528685  )
So the solution is to RMA the card ?

I recomend to all with this problem to try with this drivers

http://downloads.guru3d.com/GeForce-Forceware-259.31-Win-7-%7C-Vista-64-bit-download-2603.html

for me work fine for now im still testing ...

my computer freezes even though i uninstalled the drivers. so it's freezing using windows default vga drivers. does this happen to anyone else?

I have this exact same problem.  I was in process of RMA, but canceled it cause i thought it was fixed!

For those who think you fixed problem, doubt it.  I thought mine was fixed for 2 days. Than BAM! Hard lock in BC2 reset, hangs out welcome screen 4 times in row.  I said "forget this" and went to work, came home turned on PC and was like "oh its working".  BAM! 2 hours later hard locks up opening a movie in VLC. 

It has to be a driver issue, my "old" GTX 260 works fine 2nd i put it in.

Maybe the "added support for 460" cards in patch notes was not right..

hypermog

I have not tried this since I don't have my card, but here are some instructions I've gathered from reading forums:


Uninstall your current drivers in safe mode.


Download the 259.32 beta driver here:
http://www.nvidia.com/object/geforce-3d-vision-winvista-win7-cd-1.34-beta-driver.html

extract the zip and delete these files below:
\NVIDIA_3D_Vision_CD_v1.34_International_update\Drivers\WinVista64\hdaudio_1.0.15.0_xp_vista_win7.exe
and
\NVIDIA_3D_Vision_CD_v1.34_International_update\Drivers\WinVista32\hdaudio_1.0.15.0_xp_vista_win7.exe

then install the driver by running:
NVIDIA_3D_Vision_CD_v1.34_International_update\Drivers\setup.exe

See if that helps at all...

Ultimately, following the instructions and installing the driver mentioned by hypermog is what seems to have solved the issue with my system (GPU = GTX 460 1GB SC EE).  Below, I'll give a brief overview of the symptoms my computer was experiencing, things I tried to do to fix the problem, and the final solution that seems to have brought stability back to my system (no significant crashes in the last two days compared to tens of crashes per day the previous 7 days).
 
For the first couple of weeks with the GTX 460 in my system, I had no noticeable problems.  The problems then started with a sudden crash (read: hard reboot with no warning) while watching a YouTube video.  I thought this was a fluke, but the problem became progressively worse over the course of a week or so.  It first started crashing on just Flash videos online (YouTube) with Bugcheck code 0x116 (VIDEO_TDR_ERROR likely caused by the module nvlddmkm.sys).  Then I noticed the problem with other video playing including Silverlight and DVDs via Windows Media Player (again, with Bugcheck code 0x116 caused by nvlddmkm.sys).  As time went on, doing mundane tasks such as moving an open window would cause a crash.  I never actually saw a blue screen, my monitor (an HDTV connected to the GPU via HDMI) would just go black followed by a reboot (the BSOD was logged by Windows though).  Eventually, the crashes became more frequent to the point where the system would freeze at the welcome screen and my computer had become all but useless.
 
My troubleshooting efforts included re-downloading the Nvidia 258.96 drivers, uninstalling the Nvidia drivers on my system (followed by safe mode cleans using Driver Sweeper), reinstalling the 258.96 drivers multiple times, updating my mobo BIOS, tweaking memory settings, tweaking various mobo BIOS settings, running Memtest 86+ and other diagnostic tools, disabling the 4 High Definition Audio devices (Computer Management->Device Management->Sound, video and game controllers), uninstalling Flash and all other Adobe software, uninstalling Silverlight, etc.  I wasted many precious hours tweaking my system and searching forums for a solution.
 
After exhausting just about every possibility and counting out other components through various testing (memory passed various tests, no errors seemed to single out the CPU, my PSU was providing stable consistent power across all rails, ambient system heat was not an issue and neither was any single component overheating, I did not have anything overclocked - not counting the stock overclock from the GTX 460 SC), I began to think that the GPU might actually be failing.  However, I was having a hard time convincing myself of this because I didn't see any of the telltale signs of a failing GPU such as overheating, artifacting, crashing during actual effort such as 3D games, etc.  Then I ran across several forum entries of people claiming that the 259.32 beta drivers helped to alleviate similar issues to what I was experiencing.  I'm not a fan of installing beta drivers onto my system, but I'm even less of a fan of my computer continually crashing, so I decided to try it following hypermog's instructions.  Miraculously, my system has been relatively stable now for two days.
 
In short, these are the final things that I did to my system to bring back stability (please note that I did all of these same things with the 258.96 drivers as well and they had no significant effect, so most of the steps here may not be necessary save for the installing of the 259.32 drivers).
 
- Uninstalled all Adobe Flash related installations
- Uninstalled Silverlight
- Uninstalled All Nvidia graphics and PhysX drivers
- Removed any left over components using Driver Sweeper in safe mode
- Ensured onboard sound was disabled in my BIOS (I'm not using onboard sound)
- Installed the 259.32 drivers following hypermog's post above
- Disabled all 4 High Definition Audio devices (read post #4 here for more details http://forums.evga.com/tm.aspx?m=525354&mpage=1)
- After testing my system successfully with no crashes for a day, I installed the latest versions of Flash and Silverlight.  Still no crashes so far.
 
Your situation may be different than mine and the above may not solve your issues, but hopefully it will help point you in the right direction if you are having crashing issues with the GTX 460 or similar card. Good luck.
EDIT: 1/22/2011
My card has started malfunctioning again with the same errors and symptoms previously described.  I followed my instructions above to try and "reset" things, but no luck this time around.  Very frustrating.

hi
 
i have the same problem  constant freze after  upgrade to gtx 460 sc, all fixed now 
try this
http://worldofexception.blogspot.com/2008/12/com-surrogate-has-stopped-working-fix.html  "site crash in internet 9 beta so use any other to see " 
 
no more crashes  after that  , im using  windows 7 ultimate x86  with  260.63 and onboard sound
 
 
hope it can help 
good luck