Visiontek 4850 - Bad overclocks?

[qwertyaas]

Anyone experiencing really bad overclocks with the Visiontek 4850? Is it because they use a lower stock voltage?

It seems that my card starts artifacting bad in ATITool at around 670/1050 with temps of mid 60c. I tried two cards so far and both yielded the same results (both VT cards).

Is it the stock cooler or just the voltage settings on the card? (I tried my latest OC test at 65% fan speed).

[Jakalwarrior]

Since the boards are mostly identical couldnt you try a different manufactuers bios?

[qwertyaas]

I was considering that, but was curious if the (2) cards I got were just "bad" cores, or it is just the stock settings for Visiontek cards.

[Heretic]

I'll try to find the post, but the VisionTek cards supposedly do use a lower voltage. I think flashing to the MSI bios fixes that.

edit: Here it is : http://www.xtremesystems.org/forums/...&postcount=277

[qwertyaas]

Ahh I see. So I guess there is no point trying to exchange it for another Visiontek 4850 in Bestbuy.

Right now it seems like I top out close to 670/1050 before I get a massive amount of artifacting in ATITool - Temps reaching mid 80c with fanspeed at 40%.

[qwertyaas]

Quick question though. If I swap out identical cards, should I reinstall the drivers as well or no need?

[jimmyz]

Quick question though. If I swap out identical cards, should I reinstall the drivers as well or no need?

mine do better. and are VT also. one did 700 and the other wanted to drop the core at 690 or above. but artifacting wasn't an issue. I would worry about the PSU before exchanging cards. I think it is underpowered for an overclocked rig. I am assuming the cpu is also overclocked.


EDIT : I was assuming crossfire, since you mentioned both cards. sorry for 1 you should be fine.

[qwertyaas]

O no, just running a single card. Meant if I should reinstall the drivers after I swapped the old 4850 for the new one (same exact cards).

[jimmyz]

nope not unless there is some problem.

[qwertyaas]

Alright thanks. So far the card seems better temp wise. Idling 8c lower than the previous (45c at 45% fan speed). Time to check out the OC now!

Looks like it is a voltage issue. Even with much lower temps on this card, I'm still hitting a wall around 660/1050.

[Rattle]

with msi stock bios my cards did 685/1075

they wouldnt do it with visiontek bios, i also measyred gpu and mem volts off the card before and after and msi gives a small bumop for some reason.

[qwertyaas]

After checking my BIOS settings in RBE, seems that my card has stock volts of 1.046/1.084. Guess that does explain the low OC limits on the card.