PCIe x4 ?

bonanza

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Is it important to have a PCIe x4/8 for future upgrade (non-video card) ?

From what I see most of mobo today provide PCIe x1 expansion slot rather than PCIe x4 (or even x8). I assume PCIe x1 will replace PCI. Then what is this x4 for, will it replace x1 ?



Thanks.
 

Fullmetal Chocobo

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Granted, everyone is going to do their own thing, but one of the biggest problems for me right now in finding a mobo is that I want to use a PCI-e 8X RAID card (Areca ARC-1220). The 680i motherboards are a prime candidate (and I have confirmed reports that the RAID card works on the Asus P5N32-E SLI).

For some, it is going to be very important. For others, it isn't. If you think you might need it later, then I definitely would consider than in researching future upgrades.
 

tcsenter

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PCI-E x1 has approx. twice the peak bandwidth of PCI conventional (250MB/sec v. 133MB/sec), so PCI-E x1 is more than sufficient for virtually any consumer device that currently goes in PCI conventional. Note: That is 250MB each way in bidirectional traffic, for a total transfer rate of 500MB/sec.

PCI-E x4 is most suited to something like very high-end storage adapters (RAID, NAS, SAS, SCSI, et. al.), multiport managed router/switch networking cards, very high-end video capture or multi-channel DVR cards, or a secondary graphics card for multi-display. Emphasis should be placed on 'very high-end'. I am referring to enterprise, carrier, or commercial class stuff often costing thousands of dollars.

PCI-E x4 has approx. 2GB/sec transfer rate (1GB/sec bandwidth each way). What are you intending to put in that?
 

bonanza

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Originally posted by: tcsenter
PCI-E x1 has approx. twice the peak bandwidth of PCI conventional (250MB/sec v. 133MB/sec), so PCI-E x1 is more than sufficient for virtually any consumer device that currently goes in PCI conventional. Note: That is 250MB each way in bidirectional traffic, for a total transfer rate of 500MB/sec.

PCI-E x4 is most suited to something like very high-end storage adapters (RAID, NAS, SAS, SCSI, et. al.), multiport managed router/switch networking cards, very high-end video capture or multi-channel DVR cards, or a secondary graphics card for multi-display. Emphasis should be placed on 'very high-end'. I am referring to enterprise, carrier, or commercial class stuff often costing thousands of dollars.

PCI-E x4 has approx. 2GB/sec transfer rate (1GB/sec bandwidth each way). What are you intending to put in that?

Actually I don't plan to use any of those 'very high end'. I am just worried if in the near future ALL of the cards will be x4 (x4 will be standard instead of x1), so any mobo that doesn't have at least x4 can't upgrade/expand.

I was going to take an SLI mobo, not that I want to go SLI, but to reserve the slot for future x4/x8 cards. But if the cards cost thousands of dollars (very high end), maybe I will drop this SLI thing.


 

bonanza

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Originally posted by: Fullmetal Chocobo
Granted, everyone is going to do their own thing, but one of the biggest problems for me right now in finding a mobo is that I want to use a PCI-e 8X RAID card (Areca ARC-1220). The 680i motherboards are a prime candidate (and I have confirmed reports that the RAID card works on the Asus P5N32-E SLI).

For some, it is going to be very important. For others, it isn't. If you think you might need it later, then I definitely would consider than in researching future upgrades.

Why do you have to go 608i, isn't any SLI/crossfire-enabled mobo have a second PCIe x16 that can be used for x1/x4 and x8 ?

Thank you all for responding.
 

tcsenter

Lifer
Sep 7, 2001
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PCI-E x1 will replace PCI conventional slots eventually, though not anytime soon since the PCI bus has in a sense been given a new lease on life. With chipsets providing more integrated storage connectivity and RAID capacity (up to six on some boards, and more are provided by an external controller chip), it significantly decreases the demand for add-in PCI storage controllers.

A few other traditionally PCI devices are moving or have moved off the PCI bus to chipset integrated busses or interconnects. This has freed up the PCI bus to an extent, leaving it more than enough bandwidth for relatively low throughput devices like modem, WLAN, and sound cards, and USB2.0 or firewire controllers.

At any rate, PCI-E 4x will not be a 'mainstream' device for at least a few more years. You can see this by how many boards currently have PCI-E 4x and among those you might get one PCI-E 4x slot on a board but not more.

Besides, PCI Express is nearing its second revision that will double data/signaling rates across the board. Meaning, in two years (or less), the PCI-E 1x slot will have twice the bandwidth it has now (500MB/sec each way).
 

bonanza

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Originally posted by: tcsenter
PCI-E x1 will replace PCI conventional slots eventually, though not anytime soon since the PCI bus has in a sense been given a new lease on life. With chipsets providing more integrated storage connectivity and RAID capacity (up to six on some boards, and more are provided by an external controller chip), it significantly decreases the demand for add-in PCI storage controllers.

A few other traditionally PCI devices are moving or have moved off the PCI bus to chipset integrated busses or interconnects. This has freed up the PCI bus to an extent, leaving it more than enough bandwidth for relatively low throughput devices like modem, WLAN, and sound cards, and USB2.0 or firewire controllers.

At any rate, PCI-E 4x will not be a 'mainstream' device for at least a few more years. You can see this by how many boards currently have PCI-E 4x and among those you might get one PCI-E 4x slot on a board but not more.

Besides, PCI Express is nearing its second revision that will double data/signaling rates across the board. Meaning, in two years (or less), the PCI-E 1x slot will have twice the bandwidth it has now (500MB/sec each way).

Thank you.
Does it mean the current x1 slot will have twice of its bandwidth by...say, updating BIOS ? or it is just for new coming mobo ?

 

Fullmetal Chocobo

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Originally posted by: bonanza
Originally posted by: Fullmetal Chocobo
Granted, everyone is going to do their own thing, but one of the biggest problems for me right now in finding a mobo is that I want to use a PCI-e 8X RAID card (Areca ARC-1220). The 680i motherboards are a prime candidate (and I have confirmed reports that the RAID card works on the Asus P5N32-E SLI).

For some, it is going to be very important. For others, it isn't. If you think you might need it later, then I definitely would consider than in researching future upgrades.

Why do you have to go 608i, isn't any SLI/crossfire-enabled mobo have a second PCIe x16 that can be used for x1/x4 and x8 ?

Thank you all for responding.

Well, since this is a gaming computer I'm building, I wanted to have two PCIe x16 for SLI, and then another PCIe x8 for the RAID controller.
 

tcsenter

Lifer
Sep 7, 2001
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Originally posted by: bonanza
Can I put a PCIe 2.0 card into PCIe 1.0 ? will there be bottleneck ?
PCIe 2.x is designed to be backwards compatible with current PCIe 1.x architecture, but you know how backwards compatibility goes in some specific instances. A bottleneck would only occur if the device itself can equal/exceed the bandwidth of the slot/bus it runs on.