"Travis King" said:
Is there a way to up the voltage to the RAM and if so how? I have an Asus
A7V333 motherboard with BIOS version 1017. I have PC-3000 RAM. I'm trying
to overclock my Athlon XP 2400+. Also, what is optimal mode and what is
turbo mode. Thanks in advance.
From the Mushkin DDR Mainboard Qualification web page:
******************************************************
ASUS A7V333: VIA KT333 chipset (VIA website)
We have qualified the ASUS A7V333 as a representative board of the VIA
KT333 chipset-based mainboards. Since the board supports DDR 333 (PC2700)
we recommend using high end memory only, that is, either PC2700 or Level2
(222) PC2100.
USER TIPS: (Note: these tips were found on the first generation of the
A7V333 in 2003, your board may be a newer revision and they may not
apply.) The default memory voltage of jthe A7V333 is out of spec which
causes DDR DIMMs to run hot and eventually fail. The voltage can be
adjusted by moving the undocumented jumpers JP1 and JP2 to close 1-2 or
else remove both jumpers completely. We found the following voltages
when measuring directly at the DIMM slots:
ii 2.59 - 2.63V (same with one or both jumpers removed completely)
i! 2.78 - 2.83V (default setting, out of spec according to JEDEC guidelines
!i 2.88 - 2.94V
!! 2.95 - 3.06V
Click here for location of jumpers on board.
Click here for close up of jumpers.
The latter two settings are almost guaranteed to destroy the memory
modules. We found that by reducing the voltage from default to the
lowest setting, we were able to achieve approximately 3% system
performance increase (not in SiSoft Memory benchmark, though but in
real applications)
We found that running the memory bus asynchronous at 166 MHz with
the FSB does not overall increase system performance because of the
higher latencies and the buffers required for synchronization of
memory and FSB. Many of the boards exhibit some problems when DIMM
Slots 1 and 2 are populated simultaneously. Moving the DIMMs to slots
1 and 3 usually solves these issues.
******************************************************
Note: the letter "i" means put the jumper in the lower position, and
the "!" means put the jumper in the upper position.
A close up of the jumper is here:
http://www.mushkin.com/gif/a7v333jumpers.jpg
I would have given a URL to the above info, but the Mushkin links
contain a cookie, which makes deep linking impossible. The cookie
becomes stale in a couple hours, and writing up instructions on
how to formulate a link is a waste of time.
As for modes, I cannot tell you exactly what they do, as I don't
think it is documented anywhere. On some Asus motherboards, Turbo
is a shortcut for setting the RAM timings to 2-2-2, and unless you
had some BH-5 or BH-6 memory, isn't likely to work.
If you want some perfectly worthless info, try clicking the Subject,
Problem, Answer buttons on this page, then enter "turbo" in the
search box. I guess they don't know either - they give as precise
an answer as I just gave
http://www.asus.com.tw/support/faq/faq.aspx
Better to experiment by using manual memory timings, to see what the
memory can do. Whatever your Trcd setting is, increase it by one, if
you are attempting to push the ram clock past the spec value. Of
course, all the timings have to be adjusted for speed. For example,
at PC3000, the clock is 187.5MHz and clock period is 5.33ns. If the
memory was CAS2, the time would be 2*5.33=10.66ns. If you ran the
memory faster, the product of CAS and the new clock period would have
to be greater than or equal to that time. So, at 200MHz (5ns period),
the closest setting would be CAS2.5, as 2.5x5=12.5ns and that is the
least product greater than 10.66ns. CAS varies in half integer values,
and the others vary in integer values. If in doubt, try 3-4-4-8.
Verify each setting with memtest86, as booting the OS with bad memory
settings, or too high a PCI clock frequency can lead to disk corruption
so bad, you can lose the disk (it happens - check Abxzone). PCI
shouldn't be pushed past 37.5MHz, and you'll need to read up on what
dividers your board supports for overclocking, to know what risks
you are running with regard to FSB.
HTH,
Paul
