At first I wanted to make a video of some fuzzy markings that appear on my screen after the update, and I think they mostly appear after I leave the water, although they do appear sometimes randomly. Its hard to distinguish them from a picture hence the video. I happened to record the "can't see underwater" bug too.

Please watch in 720p HD, and look at the character after he leaves the water, you will see some blurry lines on the screen. 3 to his right and 2 on his left.

http://www.youtube.com/watch?v=WOS8xvwCATk&feature=youtu.be

I dont have any mods installed. I hope its visible

No clue what that is, but you can see it.

Video card? Driver version?

You say 'no mods' but also check you do not have a d3d9.dll in the same folder as your TESV.exe.
Also reset your video driver settings to defaults; don't force such things like Anti-Aliasing through the driver panel.

Most reports of this nature have either involved AMD cards or some rogue d3d9.dll.

Wow, thanks alot! I actually did this fix a while back to fix my lag http://www.youtube.com/watch?v=KseYGybhOck&feature=related basically I had to put another d3d9 file in my skyrim file. It worked fine until this update. So I deleted it now and restarted skyrim, allowed it to detect my graphic card, and sure enough both bugs are gone now thanks again.

my water effects look great now! http://cloud.steampowered.com/ugc/576699622615864674/3B0F8B6A4F5040E283EF9B9C324C65D6B94E4090/

Where is d3d9.dll in Skyrim directory? I don't see him ... :/

for me I found it here
C:\Program Files (x86)\Steam\steamapps\common\skyrim

Ok, thanks ... I don't have that file... But my GPU is a ATi radeon, so I'm confuse ...

@kabtq9s: What's your GPU, BTW ?

AMD Radeon HD 6770

Thanks ... This can be very helpful for AMD's GPU users.

I'll clarify. On a normal install you DO NOT have, or want, a d3d9.dll in your Skyrim folder.

Some people create a modified d3d9.dll that can fix specific problems with bad drivers (the poster here) or add more features (the ENB series of mods).

Putting such a modified .dll in the same folder as the .exe forces the game to use that file instead of the standard DirectX that come with Windows.
If you forget you are using someone's custom file you can run into problems when Bethesda make changes to their graphics engine in an update.

Many thanks for your clarification. This explains a lot.
In fact I never use ENB series and the game recognizes my GPU. I wonder if the most problems people have are not due to have the file d3d9.dll in Skyrim directory ...

Just to clarify, I don't have problems with Skyrim, but I with 1.4.27 yet. "Fear" to go online mode in Steam, until some mods also update to 1.5.24. But I like to search for information available before, in case I experience problems in the future.

Now I'm having problems with lag again because the game is not recognizing my GPU, which is why I installed that d3d9 file in the first place. Oh well, I guess I will make another thread about this issue.

Just a thought. Perhaps the game is not recognize your GPU because this 3 files (in username\my docs\mygames\Skyrim)...

RendererInfo.txt
Skyrim.ini
SkyrimPrefs.ini

...are read-only?

If so, you can try delete them and launch the game again to re-create new ones...

nope, I deleted them and restarted skyrim, it only detects my intel GPU

I am having similar issues with dead or missing pixles in high light areas. I was running the beta 1.5 fine, but after the latest patch, i started having this problem. I did as suggested, found a d3d9.dll file and deleted it. But I am still having problems. I noticed there are other .dll files in the skyrim folder. Will deleting these solve my problem?

The missing square pixels are due to an AMD driver bug.

you need to get rid of the d3d9 file , it does not come with the skyrim install , it can and will cause fps drop if it is poor mod or one youve found of the net , if your using ENBseries go here http://enbdev.com/index_en.html for newest updates , or if you are using RCRN http://skyrim.nexusmods.com/downloads/file.php?id=1875#content
i would not use random DX9 files found of website because they could be old or unstalbe of not made for your g card.