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(COAST) Intel Corporation attempt to'sstandardise the modular L2 cache subsystem inPentium-based computers.A COAST module should be about 4.35" wide by 1.14" high.According to earlier specifications from Motorola, a modulebetween 4.33" and 4.36" wide, and between 1.12" and 1.16" highis within the COAST standard. Some module vendors, includingsome major motherboard suppliers, greatly violate the heightspecification.Another COAST specification violated by many suppliersconcerns clock distribution in synchronous modules. Thespecification requires that the clock tree to each synchronouschip be balanced, i.e. equal length from edge of the connectorto individual chips. An unbalanced clock tree increasesreflections and noise.For a 256 kilobyte cache module the standard requires thesame clock be used for both chips but some vendors useseparate clocks to reduce loading on the clock driver andhence increase the clock speed. However, this createsunbalanced loading in other motherboard configurations, suchas motherboards with soldered caches in the system.