question about kt333 & nforce615

[DamienV]

I'm undecided between buying a board w/ kt333 or nforce615 chipsets: on one hand the KT333 has ata133, ddr333, usb2, and its available!... The nforce615 althow still not available (witch is irrelevant since i'm waiting for XP's 0.13u) will also have ata133(?), usb2(?), and ddr333. My question is: how much will the 5.4Gb/s of the nf615 help the video board when compared with the 2.7Gb/s of the kt333? Very much? So-so much? Not that much? I'm planning to buy 2 ddr333 sticks anyway so this is not a consern.

 

[BD231]

Unless your using on board video, that 5.4gb's of bandwith will go unused. Athlons can only use 2.4gb's of bandwith so you would be fine with even a KT266a. However, I would go for the 615 chipset if you can find it for a good price.

 

[Athlon4all]

Well KT333 and 615-D are not integrated chipsets so I don't think that's what you mean. To be quite honest, you will not see a real world difference in any application unless integrated video is involved between VIA KT266A with DDR266, KT333 iwht DDR333, nForce 220-D, or 420-D with DDR266, or 615-D or 620-D. The Athllon's fsb is maxed out with DDR266 and DDR333 is pointless except on platforms with int. video like 620-D or 420-D.

 

[DamienV]

U pple mean that an external AGP4x vid card wont take advantage of the extra bandw/ provided by something else other than a single stick of 64bit of ddr266?? What if we where talking about AGP8x?

 

[Mingon]

The transfer speed between the agp car and its port do not effect the main memory. Although the video cards can use the system memory for agp textures this is not that common (corrrect me if i'm wrong) as has been pointed out the limit on the Athlon is the fsb speed i.e 266mhz / 2.1gb/second and as such pc2100 is a perfect match. The move to ddr333 is slightly pointless as the two bus speeds run asynchronous (different speeds to each other) but an improvement can be seen of upto 5% probably as DDR memory is not 100% bandwidth efficient. I personally Have just bought a kt333 based epox board with the wish to run it at 166mhz to allow the processor more fsb bandwidth.

 

[BD231]

The transfer speed between the agp car and its port do not effect the main memory. Although the video cards can use the system memory for agp textures this is not that common (corrrect me if i'm wrong) as has been pointed out the limit on the Athlon is the fsb speed i.e 266mhz / 2.1gb/second and as such pc2100 is a perfect match. The move to ddr333 is slightly pointless as the two bus speeds run asynchronous (different speeds to each other) but an improvement can be seen of upto 5% probably as DDR memory is not 100% bandwidth efficient. I personally Have just bought a kt333 based epox board with the wish to run it at 166mhz to allow the processor more fsb bandwidth.

The extra bandwith of the KT333 is pointless, it will actualy produce higher latency if you run at 166mhz which will end up slowing you down unless your CPU is running at the same fsb clcok. But you might as well buy a KT333 board considering they dont cost much extra and have some nice new features like the USB 2.0 and all that. Just remember not to run your mem any faster than your CPU.

 

[Mingon]

<< However, the tests we carried out for VIA KT333 showed that in reality things are completely different. The use of DDR333 memory instead of DDR266 increases the performance of Athlon based systems by 3%-5%. It happens because the protocols transferring the data along the processor bus and the memory bus are different and the memory subsystem features much higher latency than the CPU. >>

quote from xbitlabs



<< The current DDR266 chipsets don't deliver completely on their promise of 2.1GB/s of throughput, so there is a little room for improvement. On top of that, components in the system other than the CPU can make use of extra memory bandwidth, even if the CPU is bottlenecking on its front-side bus. Hard drives and other I/O devices will use direct memory access (DMA) to read and write data to memory without passing data across the front-side bus. >>

From techreport

 

[Athlon4all]

<< U pple mean that an external AGP4x vid card wont take advantage of the extra bandw/ provided by something else other than a single stick of 64bit of ddr266?? What if we where talking about AGP8x? >>

Sadly yes. And it goes further than that. Like I said, the Athlon's fsb is allready being used to the max by DDR266, so the extra bandwidth provided by DDR333 and nForce's Twinbank won't help at alll really compared to KT266A.

P.S. Bdog, just fyi, the Athlon's fsb is 2.1GB/ps (133 (MHz) x 2 (DDR) x 64 (width of the bus)/ 8 (conversion of bit to byte) = 2.1GB/ps

 

[DamienV]

I guess i'll buy a7v333 fited w/ 512Mb ddr333 C2 Corsair mem and stick a 0.13u XP in it OC'ed at 150/166Mhz FSB. I just dont know if the ASUS mboard has a /5 divider to keep the PCI bus at 33Mhz... do you? Do you think an Alpha PAL8045 w/ a 80mm Delta 4000rpm fan will keep it cold enough? What do you think of www.newegg.com? Are they any good?

In case i forget later on, thankx for any and all kinds of help.
Damien Vessa

 

[Mingon]

Just got my epox kt333 board, using an unlocked 1.1tbird I have just run it at 7 x 166 without a problem, using crucial pc2100 running at 166 cl2.5 As far as I can tell the 1/5 divider is working as I doubt my scsi controller could run at 41.5mhz pci bus.