oclHashcat-plus sees only 2GB on sapphire HD 7950 vapor-X
#1
I have a brand new GPU with 3GB of memory but when I launch the oclHashcat-plus, I can see this output:

Hashes: 1 total, 1 unique salts, 1 unique digests
Bitmaps: 8 bits, 256 entries, 0x000000ff mask, 1024 bytes
Workload: 4096 loops, 800 accel
Watchdog: Temperature abort trigger set to 85c
Watchdog: Temperature retain trigger set to 80c
Device #1: Tahiti, 2048MB, 950Mhz, 28MCU
Device #1: Kernel ./kernels/4098/m0400.Tahiti_1124.2_1124.2 (VM).kernel (86896 bytes)
Device #1: Kernel ./kernels/4098/markov_le_plus_v1.Tahiti_1124.2_1124.2 (VM).kernel (88664 bytes)
Device #1: Kernel ./kernels/4098/bzero.Tahiti_1124.2_1124.2 (VM).kernel (30456 bytes)

Other tools like gpu-z report correctly 3GB. Any idea where the problem could be?

I also experience drop of core clock from 950MHz to 850MHz or even more together with drop of load from 99% to 66%. The performance drop does not occur when having the boost button switched off which means the core clock is stable at 850MHz and the load is also stable at 99%. Any idea why this is happening? The attachment shows the unstable case. Thx!


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#2
AMD's OpenCL runtime does not allow the use of all memory, see this: https://twitter.com/hashcat/status/373100787108282368
#3
I don't clearly see explanation for my problem in that tweet. Maybe I am a really big newbie. Big Grin Anyway thx for your reply.
#4
the explanation is that you need to set an environment variable or two to use all available video memory.
#5
Yes, it helped me to increase used memory to 3GB but the speed is still the same. Sad No idea why. Anyway thanks for replying.
#6
it won't affect performance, no. it will only help you e.g. load larger hash lists