S460 533 MHz memory upgrade still runs at 400MHz

Greeetings all,

I recently upgraded my S460 with two 512MB sticks of PC4200 DDR2 (533 MHz) memory from Patriot. The memory is recognized just fine, but apparently the BIOS is not adjusting the memory bus to the faster speed this memory supports. Both CPU-Z and SiSoft Sandra report that the memory is running at 400 MHz, not 533 Mhz.

Can anyone who has upgraded their S4XX series laptop with 533 Mhz Pc4200 memory confirm that the memory is in fact running at the higher speed? CPU-Z is the easiest tool to find this out.

I suspect that the BIOS of this laptop may not be configured to allow higher memory bus speeds, so I wonder if there is a way to edit the BIOS to allow a 266 MHz memory bus block setting (for 533MHz DDR2 memory)...

Regards,
-Robert Hildinger

 

Of course it runs at 400 MHz. S3xx and S4xx only have 400 MHz memory bus. S5xx is the first S that supports 533 MHz memory bus.

 

FYI, when running in dual channel mode with the i915 chipset the memory runs at 400MHz.

 

Yeah, I just took a look at the Specs and it does say that 533 MHz Dual channel is possible. I was told that DC is only available at 400MHz. I'm not aware of any machines where DC runs at 533. I know that the XPS2, GW M680, Sony Sxxx, etc all run at 400MHz in DC mode.

 

then the obvious question is "which one is faster?"

 

Well, I switched out the two PAtriot 512MB SODIMM's and replaced them with two 1GB OCZ SODIMM's. As expected, the result was the same with the memory bus running at 400 MHz, although the OCZ memory appears to perform a *little* better than the Patriot.

So we know that the memory bus to FSB clock ratio appears to be locked by the BIOS at 3:2, which for a FSB of 133 MHz results in memory bus speed of 200 MHz (400 MHz eeffective for DDR). Obviously what we need is a 2:1 clock ratio to achieve the full 533 MHz memory bus speed.

The new S5XX series *appears* to support the 533 MHz memory bus speed, which means the BIOS is slightly different from the S4XX series. I highly doubt that there any real differences in the motherboard though, which leads me to wonder if it would be possible to flash an S4XX series with an S5XX series BIOS to gain the higher memory bus speed. Would it be worth it in the end?

FWIW, I've tried editing the S4XX series BIOS in the Phoenix BIOS editor, but finding the part that controls clock speed ratios is a bit beyond my skill. Anyone else want to give it a shot?

-Robert Hildinger

 

has anyone just tried one stick of DDR533??

 

Either way, having the extra bandwidth is pointless, because the front side bus can handle only 533 mhz of data, which single channel memory can provide just fine.

 

I know this is a really stupid queston, but i need to ask it as not to screw up my new computer. Where does the 2nd ram stick go, all i seem to have access to is the wifi card and 1 stick of ram. Please be so kind as to tell me what to remove, as i Just bought 2 gigs of ddr2 memory.
Thank you.

 

Well I've undervolted, updated the Bios and installed the latest video drivers. I now have a much cooler more functional S460 !!!

Now for more memory....I installed a DDR2-4200 1Gig stick that still runs at 400Mhz as you have seen. Has anyone found a way to change the FSB-DRAM setting from 2:3 to 1:2 or 2:4? I really don't want to overclock the whole FSB and system clock....

 

http://www.laptopvideo2go.com/forum/index.php?showtopic=8563