Overclocking Ati Mobility Radeon 5850?

Hey there guys! I'm new to the forums and I think I may have bumped a thread from the dead with this question, so sorry in advance...but I'm wondering:

Is it safe to overclock the 5850MR to 5870MR stock clocks? (if so, how do I do it?)

I know I can overclock it to 5870 stock clocks, but how do I go about it, and will it run cool enough to be safe? I apologize as I'm an O/C noob. I own the alienware m15x, so if anyone has any specific advice, please feel free to help a guy out . If anyone with experience has a guide or something they could contribute I would be most grateful.

Best Regards,

Kojaku

 

Each card and system is different. You need to clock yours up slowly and test the temperatures and see what it can handle.

You will need this program: AMD GPU Clock Tool v0.9.26.0 For HD 5870 download from Guru3D.com

 

And what would you say is a safe temp? Is temp the only indicator of how stable the O/C is?

 

I have OCed 5870 (840/1090@1,02V) in my laptop, it heats up to 85C at 100% load on a hot day (using BOINC DistributedNET or FurMark), never had any problems with artifacts or instability.

That's just to give You some general idea.

If You temps are good, You can overclock 5850 way beyond 5870 clocks, some people from this forum have OCed 5850 to clocks similar to mine.

 

I've also heard you can edit the voltage. Is that necessary?

 

I have lowered the voltage on my card to reduce the heat. It had no impact on stability. It takes plenty of experimenting to find out the best balance between clocks, voltage and generated heat. This procedure is rather for advanced users only.

 

If I'm careful enough I can do it though, right? Just gotta clock it up real slow, in like 10Mhz intervals? After all, I have to learn somehow xD...

 

Just go up to 750/1050 to start with, then go up slowly.

 

I'd be satisfied with 775/1050 myself. I just wanna be able to laugh at the folks who spent extra cash on a GTX 460M. Heehee.

 

You will find all the necessary info on this forum. Don't rush things, do a lot of reading and You will be fine .

 

Yay! I'll post my results when I finish. Just for the sake of having one more point of data on overclocking the 5850MR. Thanks for all the help guys.

 

i oc my to 775/1100 had like that for maybe 3 hrs runnning nfshp and screen went black and now it wont oc to those setting... temps never went over 72 and mem hit 82, so now i just go with 750/1050 it works fine about same temps and mem never goes over 80. ill replace term paste here soon and see what happens..

 

does anyone know which tweaking tool can handle 5850 memory latencies and more advanced stuff? ATT doesn't work (crashes my acer 8942g).

 

Radeon BIOS Editor (it includes a HEX editor, You can change timings and latencies there, but I have no idea which offsets are responsible for it; they're probably different for each vBIOS).
AFAIK softmods for memroy latencies won't work, You need to modify the vBIOS.

 

thanks... but that is too dangerous in my opinion. I would prefer sliders in Windows like the old ATT on x700 worked. Actually I was getting more stable mem clocks at high freqs when latencies were set properly and benchmarks went higher too.

 

So I clocked up to 775/1050 and I used Furmark and found I was hitting 90C at Full load and right now I'm idling at like 55C. I'm swapping my stock paste for some arctic silver 5 tomorrow...so do you think this sounds like a reasonable clock setting, temp wise? (Cuz the Vbios flashing comes next...)

Kojaku

 

If the ambient temperature was high enough during Furmark and You think the chances for the laptop to operate in 'less friendly' thermal conditions are minimal, You can proceed with the vBIOS flash. The GPU can withstand 90C easily, although it is a tiny bit high. In normal operation it is very unlikely that it will reach such temperature, unless You run some intensive numbers crunching software (like BOINC) on Your laptop.

PS.
You can also experiment a bit with undervolting, to reduce heat. You can also get some decent cooling pad.

 

Hmm. Just to be safe then, as it is rather cold in my house right now (not the usual)...I'll flash the bios at 750/1050. That's at least 5870 stock level anyway

Kojaku

 

Stock 5870 clocks are 700/1000. If You want to be safer with temps, don't overclock the VRAM. GDDR5 generates a lot of heat. I'm quite sure that Your temps would be lower, if You set the GDDR5 clock at default 1000 and the core clock at, let's say 825, or even more.

PS.
What laptop do You have?

 

I have an m15x. Man, the cooling on this thing is really superior

 

Superior cooling, says You?






Superior cooling, says I!

 

740/1050 with 11.1 works fine, but not stable enough for long gaming. temps around 75

I have GDDR3 and overclocking VRAM doesn't produce any visible difference in temps for me (well it probably does go higher, but it is so little in comparison to overall temp rise and fan's ability to cope with that). GPU core rises around 3-5 degrees on 740 MHz in comparison to 625.

 

Marecki: Thats how a good cooling looks like. I'll do this whit my MSI too.

 

Thanks . If You need any advice, feel free to ask .

PS.
Before You even start, here's a little tip: majority of those small copper RAM heatsinks come with a double-sided, thermal conductive sticky tape on them. Remove it (it doesn't work well) and use some quality thermal epoxy instead (I used Arctic Silver Thermal Adhesive).