Hey guys! I have no clue as to why this is, but since I installed Firefox 12 it has been hogging memory like crazy! I admit that I am one of those people who like to have over a lot of tabs open at once. More often than not I have about 110 tabs open. This is because I like to do several things at the same time and I do a lot of researching on the web. Only recently I had 125 tabs open. Now I have grouped these into smaller groups using Tab Group or the "Panorama". This helped a little, at first. I have also closed several of these tabs and narrowed this number to about 60 tabs. At its peak it was using 2 000 000 KB of memory. Now it's more like 1 200 000 KB at most. I just restarted Firefox about 5 minutes ago and now this number is currently at 665 000 KB. It started off with about 400 000 KB and it is still raising as time goes by without me even doing anything with it. It just sits there and steals memory. :) The memory usage raises to a point where Firefox becomes almost completely unresponsive. From time to time I have to wait a few seconds before I can even click in this very text field and continue typing. I am using Windows Vista SP2, 64-bit, and 4093 MB of total physical memory according to the Performance tab in Windows Task Manager. So Firefox is using half of that memory. What's going on here? Also, this all makes the use of Tab Group feature almost impossible. It's very slow to open up the Tab Group or the "panorama". It is very slow and lagging. I have an XFX Radeon HD5850 graphics card, so I wouldn't say it's due to a slow graphics card. This one is also factory overclocked. Other specs are 2.2 GHz Intel dual core CPU, X38 Intel chipset Gigabyte board, all SATA2 disk drives from Seagate and WD, 7200 RPM, top range. The memory modules are from Corsair, 667 MHz I believe, XMS with DHX. Overall I think it's a good, solid performance desktop, and I have not had any major issues with resource hungry software except this time. Firefox has been up and running now for some additional 10 minutes and the memory usage has increased to 695 000 KB. And counting... oh no, help, it's gonna blow up my computer! ;) It's gonna launch me into space... Just a side note; I do use the hibernation mode a lot or the "sleep" button. But I have made sure it's not related to it by restarting Firefox several times and also rebooting to make sure to flush the RAM but it didn't help. I do have a brand new 4 GB kit of the same brand and model that I never used up. I felt like 4 GB was plenty enough and decided to keep that second kit as a spare. So I could technically plug in that one to get 8 GB at most out of the computer. But I think it would be only counter productive... wouldn't you agree? I think the problem needs to be tackled at its core, not worked around of or swept under the carpet. I must stop typing now... it's up at 731 000 KB now. I'm starting to feel the effects of it. Not even the memory hungry Photoshop Lightroom is using this much memory on this computer.