Alright, so we have put the X1950XTX under the cold Cascade
The main issues when overclocking this card was with the overclocking
tools support. First of all, the Memory speed cannot be raised over 1140+MHz
with any tools right now. Well it’s still higher clocked than any 1900XTX Memory
right? True, but the Memory latency on the GDDR4 of this card is tuned down
quite a lot as compared to the GDDR3 Memory on the X1900XTX. So in fact the
Memory isn’t that fast unless you can get a software to overclock it far above
1140+MHz which it is definitely capable of. At 900+MHz Core, this card is definitely
Memory Bandwidth limited.
A Voltage Mod on my ASUS P5WDH came off so I just ran the CPU
at a simple 4.5GHz speed since the main effort was at overclocking the card.
Now, the second issue I faced was that this card is extremely sensitive to certain
insulative materials such as Nail Varnish. It will get stuck at low power mode
of 1.5v Memory and 1.16v VDDCI when I used Nail Varnish to coat protect the
card. After removing it and waiting for a few days, it went back to normal again.
So people insulating the card take note.
Now the third issue I faced was that Catalyst Control Center
has to be running or else the score would drop a lot. The issue is that my VDDCI
gets stuck at the default 1.56v once CCC runs, despite my voltage modifications,
hardware or software. After all the time spent figuring out all the bugs, I
went with this procedure then.
First I started CCC. Then I opened up ATi WinClk to adjust
2D/3D clock speed to the same 650/1134MHz, as well as maximizing the VGPU. I got this software from my friend Kinc from NordicHardware so much thanks to him! All
this while, I have to keep GPU around -40C before the speed and voltages go
up to warm the card from the Coldbug. Having done that, I open up ATiTool version
Beta 1.24 and start to overclock the core only. The latest ATiTool doesn’t support
very high GPU Core clocks so I used the older version, which doesn’t support
GDDR4 clocking. So I upped the core to 927MHz, as the GPU Cascade temperature
And so I ran her through 3D Mark 05. Now, I noticed that clocking
up the Core by 10MHz doesn’t gain me much points but just 10MHz on the Memory
gave me much more. So you can really see that this card is starved for Memory
Bandwidth at 900+MHz Core. We just gotta wait till better software overclocking
support then. Kinc has modded a BIOS with the same timings as the X1900XTX but I’ve not found a program to flash the card properly. The 927MHz Core was nice, and it’s cool that it’s done on default
VDDCI as I was stuck on that with CCC runnning. 927/1134MHz
got me 17,353 pretty neat. The first thing I straightaway picked
out was that the GPU Core definitely runs hotter than my X1900XTX at the same
clock speeds. My Cascade temperature worsened by at least 5C over the X1900XTX
overclocking. Be that as it may, I have a feeling the card is running into a
power bottleneck already with these high clocks.
Well due to shortage of media samples, a wave Sayonara to the
card and see it around again!