Hello I've read the various guides and threads on overclocking this card, but so far have got no where due to a few problems. I've never overclocked anything before. Firstly this is my card: ATI Radeon 9550 Powercolor 256mb 8x AGP This is the information appearing in AtiTool 0.24 (which, by the way, is displaying no temp or fan speed information anywhere in the menus) Catalyst version - 4.3 Device ID - 4153 Chip Type - RV350 Memory Size - 256 MB Memory Bus Width - 128 MB Active Pipelines - 4 Default GPU Clock - 250.00 Mhz Default Mem Clock - 200.75 Mhz I started by trying to flash the bios to a 9600 version, but I don't know which bios to use. In the guide on http://www.techpowerup.com/articles/overclocking/vidcard/107 it says to "Download a 9600 Pro Bios which matches your card's configuration. For example, if you have Samsung 4.0/5.0 you could use the Powercolor 9600 Pro 128 MB Bios dated 2003-08-23 11:56". I don't understand this, where does samsung come into it? They manufacture the ram chips on the card or something? Or the whole card? My card is made by Ati and the chips on the card display this information: "Elixir 0408 N2DS25616BT-5T 025V0AFY TW" I googled for the longest number, but found a few pdf's which made my browser crash and some other information which consisted mainly of numbers and was of no help. Someone said to look for the speed in nanoseconds? Even if I found this, how would it help me choose which BIOS to download and flash my card with as the bios download pages contain no information on the speed (in nanoseconds?) of the memory. Basically I don't know what I'm looking for and don't understand the instructions on how to look for it. Then I tried to edit my existing bios as suggested by Nobru_rv, so I checked the max core and memory settings with AtiTool. The automatic checker just confused me even more, so I followed trog100's advice and checked them manually (after setting "apply clock immediately after moving slider"). After a few restarts from hitting the max core speed, I found that to be about 450 Mhz, according to AtiTool. Then I checked the memory max speed with the core speed back at 250 and found the maximum to be between 220 and 225, it varied (and seemed to allow a much smaller increase than the average before the appearance of artifacts, only 20 Mhz...?). Armed with this information I thought I would try to overclock it with the core at 400 and the memory at 210 for now, so I dumped the existing bios and opened it in RadEdit 1.1.02beta. This is where I got confused once again, RadEdit shows the Bios Title as: RV350LX 256MB B817D16.sa525b, which seems to be ok. But then displays the following information on the core and memory speeds: Effective Memory Clock: 398.25 Mhz (Type memory DDR) Real memory Clock: 398.25 Mhz (59 * 6.75 Mhz) Real Core Clock: 249.75 Mhz (37 * 6.75 Mhz) Hmm, so considering it was showing the memory speed to be double that what it shows up in AtiTool, I left these settings and did not make a new bios. The core speed shown in RadEdit is exactly the same as the core speed shown in AtiTool when I revert it to default (249.75), however you can see there is a big inconsistency between the two programs with the memory speed. So I am stuck as to how I can overclock this card for now. Sorry this post is so long, but perhaps others may have had the same problems, I thought I would explain it in full to try and clear it up easier. Any and all help much appreciated Thanks!