Stuck in UDMA Mode 6

Soldato
Joined
30 Jul 2005
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19,906
Location
Midlands
hey all, I got a SSD now and was about to clone over to it but thought I would run a benchmark on HDTune first.
that's when I noticed all drives are stuck in UDMA 6 mode, which is SATA 1 speed not SATA2.
this motherboard, a P55M-UD4 specs that it supports sata 300 which should be UDMA mode 7.
being stuck in UDMA mode 6 means my SSD maxes out around 155megabytes per second on the benchmark.

any ideas on how I can get to full speed with sata2?
SSD is a Samsung 830 256gb which supports sata3 I believe.

my mobo drivers are for the AHCI controller are latest ones too.
 
yes its in AHCI mode, if put in IDE mode it drops to UDMA mode 5.
I don't think its a bios setting related issue. I get the feeling it may be driver related but not sure.
 
I'm not sure I'd believe what it's telling you.

According to the Intel RST both of my SSDs (840 PRO and 850 EVO) are connected at 6 Gb/s.

HD Tune has them both as SATA II devices.
 
SATA 1 is 150MB/s; so your drive is doing more than that this suggests it's running in SATA 2. The low speed maybe your chipset is not upto full bandwidth. Or a driver/firmware issue.
 
ok even more weird now. iv cloned the driver over and now the SSD is the boot drive. OMG the difference between mechanical and SSD is just next level. cant believe how fast the pc booted up and was useable. its mad!!
more screenshots:
02-_June-2017_19-20.png

and
02-_June-2017_19-201.png


now its saying that the SSD is running in udma mode 5, that's not possible because its speeds are around 170mb/s.
oddly now it says my wd raptor driver is in udma mode 7.


somethings not right here.
 
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Are you connected to an Intel SATA port that's part of the main chipset?

Many boards have additional controllers that offer extra features and look better on paper but usually underperform.
 
yes its connected to the intel port. secondary ports are provided by Jmicron. not going there anytime soon.
I would have thought that thise drive would have saturated the sata2 interface at 300meg/s but doesn't seem to be the case.
 
hmm ran hdtune again performance seems to have crept up somewhat to a 180mb average.

could it be running slower due to garbage collection or trim? since I benched it pretty much after cloning over 50 gigs of data to it in one go.
 
yes its connected to the intel port. secondary ports are provided by Jmicron. not going there anytime soon.
I would have thought that thise drive would have saturated the sata2 interface at 300meg/s but doesn't seem to be the case.

300mb/s is theoretical burst transfer speed it wont be sustainable
average is average some file types/size transfer quicker, ie 1 large file quicker than lots of small files

try removing the wd and see if performance improves
 
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your drive is doing the right thing and definitely connected at SATA2 speeds. otherwise you won't get 279MB/s reads. thats pretty much the full bandwidth of the SATA channel taking away some overheads etc.

run the SSD again on diskmark using the 1GB file format and you get a better idea.

so nothing to worry about, its just HDtune pro is showing rubbish information.
 
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