P: Pixelated or blurry preview in Library Loupe LR 4.3

Got Lightroom 5.2 with Ph CC and most of my thumbnails and previews, develope, you name it, are a mess. All was fine when I used L 4 & updates. Have used Picaso for years for simplicity & edited in Ph 2 - 6. Have tried L 5.2 because it was free with Ph CC but after this fiasco & what seems like no attempt to fix it, shall go back to Picaso and leave others to sweat it out. My only problem with Picaso is that it is not intuitive to get to Ph CC or Qimage for editing and printing.

I've juste tested the 4.4RC and yes, this bug seems to be gone!

thx.

Good to hear from you again Dorin. The problem is unchanged and have heard nothing from adobe. Are you just assuming that they are working on it and it will be fixed in 4.4?

Must be fixed in 4.4 RC.

I have only noticed it with the DNG files. But I haven't really done any work with jpeg lately. I don't make virtual copies and I don't rate them before I'm sure re quality of the image (which is actually the issue)

A definitively get a pattern when a picture is rotated +-90 from its original file orientation. Do you make other changes over the original file. (Metadata, Virtual copy, Rating)?

By the way: has somebody checked if the issue is raw related or if it appears on jpg files as well?

I have just been referred to this forum from the adobe community forum for lightroom. I have to say that I am almost at the end of my teather. I am not an IT nerd and don't want to be. I previously used LR3 to catalog my photos and PE 9 to work them and was happy. But after a lot of advise and promotion I was talked into LR4 to catalog and develop-" make the change and you'll never look back"
First my computer crashed -it couldn't handle the raw files and LR4 ran so slowly it was unworkable. I spent hours trying to optimize its performance without success. So now I bought a whole new system- 64 bit 3.4GHz quad core processor, 16mg ram,2TB hard disk, even a separate solid-state disc to run LR4
So now the very basic function of Lightroom- the ability to scan ,rate and delete a shoot cannot be relied upon.
I agree with some of the above comments- it seems to be random photos and I feel is something to do with the rendering.( I don't take vertical orientation so have not made that association).I would describe it more as a focus issue(burry) than a pixelation. If I take the loupe view in Library and go to develop then the image focuses. If I take the blurry image in loupe view in library and zoom 1:1 then zoom out it is fixed. Last night I took a shoot of 95 images of which 1/3 were blurry and I renderered the lot as standard-sized previews and this fixed about 80% of them but not all.
Also I have been rendering 1:1 on import as I was told this would help LR4 performance - so am not sure if this is a factor
So sorry for the ranting but I just want to get on with it.
Also how will i know if this is a bug or just a problem (as i suspected) with my setup.
Do i have to keep scanning the multitude of forums?

Have to agree with you John, the problem has re-appeared.