I believe that there are 6 motherboard manufacturers that are producing the SiS 648 boards. Giga-byte has the 8SG667, EPoX has the 4SDA5, Asus has the P4S-8X, Shuttle has the AS45GT/R, Soyo is coming out with the P4S-648, and Abit has there board, the SR7-8X. Personally i wouldnt recommend the abit. Anandtech did a review and i wasnt impressed. But I am in to overclocking, it is a good board for most people, just not for overclockers.
If you want a good board check out the Asus and Gigabyte boards. The Soyo and EPoX boards should also be great. These boards probably wont be out until the middle or the end of this month. Also dont buy from an online retailer only because they are the "first" to recieve it. Wait until a reliable retailer gets it. Use pricewatch.com and resellerratings.com, u could also wait until newegg or googlegear recieve it in stock.
After doing a very quick search I did not find the Shuttle AS45GT/S or AS45GT/R board for sale at a website but you could try calling one of their North American marketing partners for more info. I have been interested in that main board. The distributor ASI in CA has the board listed in their inventory SKU:15999 at http://www.asipartner.com/
I noticed you seemed uninterested in DDR333. The Gigabyte 8SG667 SiS648 Board actually employs the same SiS 648/963 chipset as does the Shuttle AS45GT/R board. The Gigabyte 8SG667 SiS648 Board supports 3 DIMMs providing up to 3GB DDR266 memory or 2GB DDR333/400 memory while the Shuttle AS45GT/R specs 3 x 184-pin DDR SDRAM supporting 6 banks up to 3 GB PC1600/2100/2700 compliant DDR SDRAM and therefore the Shuttle AS45G appears to support 1GB more of the 333MHZ DDR-PC2700 DIMM CL2.5 memory (acheiving DDR667).
That is dissappointing. Although it is probably officially coorect it appears to be somewhat misleading to me. It contradicts the reality of article released just the day before that, Friday 8/31/02, which shows how to set the memory frequencies on the SiS468/963 Shuttle motherboard. to support DDR800. http://www.xbitlabs.com/mainboards/p4x400-sis648/
The memory enginering is so good they say they can enter BIOS and use the "CPU/RAM Freq Ratio:" menu to set CAS Latency at 3 as well as changing all the other parameters within broader ranges than usual and acheive STABLE support for a wide range of memory speeds up to DDR800. This may explain why the draft specs at the Shuttle website cited before seem to show show support for DDR667 and I have often read and anticipated support for DDR400, in spite of todays news flash that SiS will not support it.
I want one! What do you think about the Shuttle? I wonder too if maybe I should be looking to RDRAM? It's so confusing. The Shuttle AS45GT using SiS648/963 seems to be well engineered. I have read that it shold support DDRII/533. Because it supports voltages up to +0.20V and it has the capability for BIOS FSB step-less settings from 100MHz to 200MHz in 1MHz increments, it seems to be a board that may also allow one to more easily overclock a P4, assuming one can cool it. It has good HW monitoring and controls too.
I'm a network SE (CNE & MCSE) looking to make purchases for the 5-year regular upgrade of my personal primary home-desktop PC. I'm hoping this next one will last 5-years before it begins to drive me nuts like the one I am replacing. My five-year old computer is so sslllooooowwww. I am not focused on, or really knowledgeable about, the new desktop hardware. So if you can keep me informed of what you learn about this mainboard subject, please do.
Good reading! It explains any question anyone has. i really liked the divider table, this helped to clarify some of the questions I had. So any of those settings could work. How could they get the DDR 400 at a DDR 800 rating? Sorry if thats a stupid question, i am still new too all this. :frown:
No, it's worse. The boards will wqork for a few months and then just stop working for no appearent reason. They have a 75% chance of going bad and having to be returned to the manufacterer once that few working months is over.
Abit and Soyo both had a long run of boards that used cheap caps, most failed within a year. Soyo however does NOT honor their warranty. I believe Epox had a short run like that before they caught what was happening and stepped things up.
<font color=blue>You're posting in a forum with class. It may be third class, but it's still class!</font color=blue>
You can read my post of approx 11:30 in the main thread that you had originally replied to.
It is first necessary to understand that DDR400 memory is actually 200MHz DR SDRAM (ie DDR= Double Data Rate= 2x DR SDRAM therfore 2 x 200MHz DR SDRAM = 400MHz DDR SDRAM ). DDR333 is actually 166MHz RAM at double the data rate. In the article I refrenced you can see a picture of the BIOS and the RAM used being used is 166MHz or DDR333.
In the table showing the range of RAM Frequencies that can be accomodated one does not even use the actual RAM size one owns or has in the computer as one of the factors in the calculations. I believe this table is used to tweak your computer to use a RAM speed above or outside the supported speeds.
Shuttle allows for a CAS Latency setting of up to 3. This allows you to set the frequency ratio of FSB:RAM as high as 1:3 , or any fraction under that to support many sizes of RAM. Using the 100Mz FSB set to 1:3 is required to accomodate certain RAM Frequencies such as DDR600, and of course using the 133MHz FSB at 1:3 will increase the size of RAM possible in that Ratio to DDR800. While in the BIOS setup they then open the "CPU/RAM Freg Ratio" menu to set the CAS Latency.
You can look at the table like this:
The first column is the Diviver (FSB:RAM) and is a column of ratios from 1:1 then 6:5 or 5:6 with the greatest difference being 1:3. If you will convert those ratios into proper fractions using the left-hand number as the denominator or divisor and the right-hand number as the numerator 1:3 becomes 3/1 which is equal to 3 in this case. That is the trick to figuring this out and it will now become clear.
Now take that 3 and multiply it by the FSB speed to get the RAM frequency the machine is set to accomodate if that 1:3 setting was chosen.
If you are using a FSB=100MHz the memory that would be accomodated would be 3*100=300 or 300MHz (DDR600).
If you are using a FSB=133MHz the memory that would be accomodated would be 3*133=399 or 400MHz (DDR800).
That can be done to accept a wide range of memories by (A.)changing the denominators and numerators (B.) Arranging the the numbers into a fraction properly (C.) Multiplying that Fraction by the FSB speed(s).
On a side note, the link that you listed about them not supporting DDR400 was removed. The story you posted about them both supporting it however <A HREF="http://www.xbitlabs.com/mainboards/p4x400-sis648/" target="_new">(This one)</A>, says that SIS is not officialy supporting it, but their older one did unofficialy(645DX), and this one does to in reality.
If ignorance is bliss, then why is everyone so miserable?
the only thing im wonderign about, is the PCI dividers, and whether ornot you can control the PCI hardware and all...upping the FSB will also affect the PCI if it doesnt offer dividers, and i dont think shuttle offers that ...