Question for the gurus

[johns]

This one I just can't figure out. I've even talked to Gigabyte
tech support, and the gobbledy-gook gets past me.

I have a Gigabyte GA-K8NF-9 mobo that has the
nF4x chipset. The manual says it will support up
to 4 gig ddr400 ram .... BUTT ... I've read, and this
is confirmed by tech support, that if I put more than
2 gig ram, the ram will clock as ddr333. So why
would anybody do that ??? Gigabyte tech says
that will not produce a performance hit because
the chipset is limited to 333 ???????? What does
he mean by that? I know that WinXP will only
use 3 gig , but what about system cache? I think
THAT will use 4 gig, and I will gain cache size
for games so that I'm not uploading from the
hard drive during the game. The GA-K8NF-9
uses SATA 150, and the transfer rate apparently
can slow a game down, if the game is pulling
from the hard drive swap file. This is about getting
Gothic 3 off its ass, of course.

johns

 

[Mike T.]

This one I just can't figure out. I've even talked to Gigabyte
tech support, and the gobbledy-gook gets past me.

I have a Gigabyte GA-K8NF-9 mobo that has the
nF4x chipset. The manual says it will support up
to 4 gig ddr400 ram .... BUTT ... I've read, and this
is confirmed by tech support, that if I put more than
2 gig ram, the ram will clock as ddr333. So why
would anybody do that ???

It probably has to do with power requirements. The 4Gigs of RAM will draw a
lot of current (relatively speaking) from the mainboard. In order not to
draw the voltage down too far to remain stable, it's likely that you'd have
to decrease the speed that the RAM is clocked at. Faster speed requires
more power, which translates to (maybe the board can't keep the voltage
stable enough)

Gigabyte tech says

that will not produce a performance hit because
the chipset is limited to 333 ???????? What does
he mean by that?

I have no idea. The chipset is spec'd to support PC3200 (DDR400, or
200MHz). In some AMD processors, the memory controller is on the CPU. So
it's possible that the processor might be communicating with RAM at 166MHz
(DDR333) speed. In that case, overall system performance would actually
decrease slightly (but not significantly) if the RAM was running at DDR400
(200MHz).

On that subject, some people think it's best to match CPU FSB with RAM
speed, but that hasn't been true for many years. At least, it's not
something that the average user should need to worry about. In some cases,
it might increase numbers slightly on some artificial benchmark. In
real-world use though? You won't notice a difference. All mainboards (and
in some cases CPUs) support running RAM asynchronously with the CPU FSB
frequency, and there is nothing wrong with that. So assuming your CPU was
clocked at some multiple of 200MHz (correlating to DDR400), it still
wouldn't be a problem at all to run your RAM at 166MHz (DDR333).

I know that WinXP will only

use 3 gig , but what about system cache?

What about it? If WinXP will only use 3 Gig, then the system cache will be
contained in that 3 Gig somewhere.

I think
THAT will use 4 gig, and I will gain cache size
for games so that I'm not uploading from the
hard drive during the game. The GA-K8NF-9
uses SATA 150, and the transfer rate apparently
can slow a game down, if the game is pulling
from the hard drive swap file. This is about getting
Gothic 3 off its ass, of course.

johns

There is generally nothing to be gained by increasing RAM beyond 2Gigs in
Windows XP. Windows Vista though is going to be a totally different animal.
I'd state 2Gigs MINIMUM for that beast. -Dave

 

[Tweek]

Actually I believe it is not the capacity of the ram, it is the fact that
all four memory sockets are populated. The memory controller is on the CPU
in the Athlon 64. I can't find a reference at the moment, but I think that
this issue was fixed in the Venice (512k) and San Diego (1MB) cores of the
Athlon 64. I imagine all versions of the X2 would also not suffer from this
problem. Even if it does drop to 333 it is doubtful that anyone would even
notice a performance hit if there is one.

 

[DrenaiLegend]

Even if your RAM were to clock @ 333 on the FSB; utilizing the extra
large swapfile will still give you an excellent refresh rate running @
333.
Unfortunately, SATA does work agianst you with transfer speeds, but 4
GIG of RAM is super power for your Bus Speeds and allocation of logical
disk space.

 

[Paul]

This one I just can't figure out. I've even talked to Gigabyte
tech support, and the gobbledy-gook gets past me.

I have a Gigabyte GA-K8NF-9 mobo that has the
nF4x chipset. The manual says it will support up
to 4 gig ddr400 ram .... BUTT ... I've read, and this
is confirmed by tech support, that if I put more than
2 gig ram, the ram will clock as ddr333. So why
would anybody do that ??? Gigabyte tech says
that will not produce a performance hit because
the chipset is limited to 333 ???????? What does
he mean by that? I know that WinXP will only
use 3 gig , but what about system cache? I think
THAT will use 4 gig, and I will gain cache size
for games so that I'm not uploading from the
hard drive during the game. The GA-K8NF-9
uses SATA 150, and the transfer rate apparently
can slow a game down, if the game is pulling
from the hard drive swap file. This is about getting
Gothic 3 off its ass, of course.

johns

You can get the info here - try Table 45 on page 178.
Gigabyte and the other manufacturers, try in their
clumsy way, to repeat what AMD says. But you can
always try cranking past the AMD recommendations.

http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/26094.PDF

This was not fixed on the Revision E. The loading from
unbuffered modules, is hard for the address/control
bus drivers to drive. A selection of Command Rate 2T,
allows extra time for the address to settle on the bus,
but costs 20% memory bandwidth.

With 2x1GB module config, you could run DDR400 1T.

With 4x1GB module config, you could run DDR333 2T.

If you wish to experiment, try in the following
sequence, with four sticks installed.

1) DDR333 Command Rate 2T (AMD recommended)
2) DDR400 Command Rate 2T More bandwidth, should work.
3) DDR400 Command Rate 1T Even more bandwidth, but likely
to error on you.

Use memtest86+, while testing. You don't want to boot
Windows, while your memory is messed up. If two passes
of memtest86+ are clean, the second step of testing, is a
few hours of Prime95 torture test.

It must be a poorly designed game, to need 4GB of memory.

Paul

 

[johns]

It must be a poorly designed game, to need 4GB of memory.

Heh! Join the fun. Go get Gothic 3 and get in on the
screaming and swearing across nearly half the world.
In my opinion, Gothic 3 is one of the best PC games
ever written. It will make an RPG gamer out of you,
if ... .... we ever get it working right.

johns