I bought a sapphire radeon 3850 256MB a while ago because i saw in most benchies it almost performs as well as a 3870 when it's over clocked. unfortunately when i try to push mine past 705Mhz it gives me a black screen and the sound keeps repeating itself then after a while it comes right and windows tells me the video driver stopped responding. Since i am new to gfx card over clocking i would of just assumed i have a bad chip but the same thing happens on stock speeds when i try to adjust my case fan speed in game and the vram clock seems to have no impact on stability.
 
Any solutions, comments or questions would be nice

Im currently at 749/1026 with my 3850 256 but mine is made by HIS. I leave the fan on at 100%.

my 3870 is at 825/1201 MHz stable, I'm not pushing it higher as I like its sub 65C temp on load. The 3850 is nice, but I only ever had the 512 version from GeCube.
 
BTW just because somebody else reached a point doesn't mean your card can/will... However in your case try downloading and installing the newest/newish drivers, and CCC and installing them.

i've been using Catalyst drivers since about v8.1. every version has had the same results
 
UPDATE:can only get to 700Mhz now as project torque crashes my whole computer occasionally @ 705

I have a 256mb 3850, from Diamond though. It's certainly most bang for your buck IMO. Anyway, do you have catalyst 8.5 now? Are you using Rivatuner or CCC for OCing? Have you changed the fan settings (I use Rivatuner to have it set at about 60%) What's your memory at? I have mine on 700 / 1800... I've hit 750 / 2000 but it's not 100% stable and the temps go higher than I'd like (leaving the fan going full blast isn't worth putting up with my gf's complaints

currently using catalyst 8.5
CCC to OC
default fan speed
memory back to default speed (829Mhz) so i can the gpu along at 705Mhz again

Well, could be your PSU, I'm not very knowledgable about that so I can't help you there. Could be your temps. I use Rivatuner to watch my temps and to bump up the fan speed which might help you out. If your temps are soaring up to the 80s under full load then you really might want to just take it back to stock, or increase the fan speed and see if that works. Using CCC, I just go along by about 5 Mhz or so, test it w/ CCC, if it passes accept it, and then immediately test for a bit using rthdribl.

AMDGPUClockTool. Works wonders.

i think you have reach the limit of your graphics card. graphics card is different once it hit it there is no more speed you can get out of it.its not like CPU where you can add more volts easily.you will have to do a volt mod.

im at 850 and 1.3ghz mem clock, stabe as can be.. 3870 tho.
 
i must say impressed with these visiontek cards

3850 is single slot cooling thought. so cooling issue need to be addressed.